HP 54710A User's Reference Manual

page of 412

/ 412
Contents
Table of Contents
Bookmarks

Table of Contents

Quick Links

Advanced Test Equipment Rentals

www.atecorp.com 800-404-ATEC (2832)

User's Reference

Publication number 54720-97005

First edition, October 1995

This book applies directly to firmware revision 4.XX.

For Safety information, Warranties, and Regulatory

information, see the pages behind the index

HP 54710A, 54710D, 54720A

and 54720D Oscilloscopes

Table of Contents

Summary of Contents for HP 54710A

Page 1 First edition, October 1995 This book applies directly to firmware revision 4.XX. For Safety information, Warranties, and Regulatory information, see the pages behind the index © Copyright Hewlett-Packard Company 1992-1995 All Rights Reserved HP 54710A, 54710D, 54720A and 54720D Oscilloscopes...
Page 2 Notice Hewlett-Packard to Agilent Technologies Transition This manual may contain references to HP or Hewlett-Packard. Please note that Hewlett- Packard’s former test and measurement, semiconductor products and chemical analysis businesses are now part of Agilent Technologies. To reduce potential confusion, the only change to product numbers and names has been in the company name prefix: where a product name/number was HP XXXX the current name/number is now Agilent XXXX.
Page 3 4 GSa/s and a maximum acquisition memory of 32K in the A models and 128K in the D models. A four-wide plug-in, like the HP 54722A, uses four slots which allows a maximum sample rate of 8 GSa/s and a maximum acquisition memory of 64K in the 54720A and 256K in the 54720D.
Page 4 If you use a screw that is too long, it can damage the oscilloscope. • HP 54710-68703 (Opt 907) Rackmount kit, handles only. Includes M4 X 0.7 X 12 mm flat-head screws, HP part number 0515-2227 • HP 54710-68704 (Opt 908) Rackmount kit, ears only. Includes M4 X 0.7 X 14 mm flat-head screws, HP part number 0515-0435...
Page 5: In This Book
In This Book This book consists of 24 chapters, a glossary, and an index. Most of the chapters describe the various menus in the oscilloscope. These chapters contain the word "Menu" as part of their title. For example, "Acquisition Menu" discusses the various softkey menus that come up on the display when you press the Acquisition hardkey on the front panel.
Page 6 How the Oscilloscope Works Front Panel Features Acquisition Menu Applications Calibration Overview Channel Menu Define Measure Menu Disk Menu Display Menu Messages Marker Menu Math Menu Measurements Setup...
Page 8 Setup Print Menu Specifications and Characteristics Time Base Menu Trigger Menu Utility Menu Waveform Menu FFT Menu Limit Test Menu Mask Menu Histogram Menu Glossary Index...
Page 9 viii...
Page 10: Table Of Contents
Contents 1 How the Oscilloscope Works Hardware Architecture 1–10 Data Flow 1–15 Sampling Overview 1–18 Choosing Plug-ins 1–24 Choosing Probes 1–27 System Bandwidth 1–32 2 Front-Panel Features Autoscale Key 2–3 Clear Display Key 2–3 Display 2–4 Entry Devices 2–7 Fine Mode 2–8 Help Menu 2–9 Indicator Lights 2–10 Local Key 2–12...
Page 11 Contents 5 Calibration Overview Mainframe Calibration 5–3 Plug-in Calibration 5–4 Normal Accuracy Calibration Level 5–5 Best Accuracy Calibration Level 5–6 Probe Calibration 5–8 6 Channel Menu Display 6–4 Scale 6–5 Offset 6–6 Input 6–6 Probe 6–7 Calibrate 6–10 7 Define Measure Menu Define Measure Menu 7–2 Thresholds 7–4 Top-Base 7–6...
Page 12 Contents 9 Display Menu Persistence 9–3 Color Grade Display 9–5 Draw Waveform 9–6 Graticule 9–10 Label 9–13 Color 9–17 10 Messages 11 Marker Menu Off 11–3 Manual 11–3 Waveform 11–5 Measurement 11–7 Histogram 11–8 Marker Hints 11–8 12 Math Menu Function 12–3 Define Function 12–4 Display 12–7...
Page 13 Contents 13 Measurements The Oscilloscope Waveform Measurement Process 13–11 The Process Starts With Data Collection 13–12 Then the System Builds a Histogram 13–13 The System Calculates Min and Max From the Data Record 13–14 Then It Calculates Top and Base 13–15 Thresholds Are the Next Values Calculated 13–17 Finally, Rising and Falling Edges are Determined 13–18 Standard Waveform Definitions 13–21...
Page 14 Trigger Basics 18–4 Sweep 18–6 Mode 18–7 Source 18–20 Level 18–20 Slope 18–20 Holdoff and Conditioning 18–21 19 Utility Menu HP-IB Setup 19–3 System Configuration 19–4 Calibrate 19–10 Self-Test 19–14 Firmware Support 19–14 Service 19–16 20 Waveform Menu Waveform 20–3 Pixel 20–6...
Page 15 Contents 21 FFT Menu Display 21–3 Source 21–3 Window 21–3 FFT Scaling 21–4 FFTs and Automatic Measurements 21–8 FFT Basics 21–10 22 Limit Test Menu Test 22–4 Measurement 22–4 Fail When 22–5 Upper Limit 22–7 Lower Limit 22–7 Run Until 22–7 Fail Action 22–9 23 Mask Menu Polygon Masks in the Oscilloscope 23–4...
Page 16 Contents Glossary Index Contents – 7...
Page 17 Contents – 8...
Page 18: How The Oscilloscope Works
Hardware Architecture 1–3 Data Flow 1–8 Sampling Overview 1–11 Choosing Plug-ins 1–17 Choosing Probes 1–20 System Bandwidth 1–25 How the Oscilloscope Works...
Page 19 How the Oscilloscope Works This chapter gives you a brief overview of how the oscilloscope functions. This chapter is not intended for troubleshooting purposes, but rather to give you an idea of the basic hardware inside the oscilloscope, so you can make better decisions about configuring the oscilloscope when you are making measurements.
Page 20: Hardware Architecture
How the Oscilloscope Works Hardware Architecture Hardware Architecture This is a high-level look at the internal hardware of the oscilloscope. You will find a complete block diagram of the oscilloscope in the Service Guide that is supplied with the oscilloscope. Figure 1-1 is a functional block diagram of the hardware in the oscilloscope.
Page 21 4-GSa/s sample rate and 32K (128K on the D models) of memory. The HP 54722A plug-in uses four slots which interleaves four hybrids in time to give you 8-GSa/s sample rate and 64K (256K on the D models) of memory.
Page 22 TMS34010 A 32-bit microprocessor that draws data on the display. • HP custom graphics coprocessor A 16-bit coprocessor that controls the gray scale persistence mode, and also writes blocks of data (like the markers and display background) to the display.
Page 23 FIFO and HP-IB Hardware The FIFO is a first-in-first-out memory that transfers waveforms through the HP-IB bus under hardware control. This hardware control is much faster than the software control used by other oscilloscopes.
Page 24 How the Oscilloscope Works Hardware Architecture Centronics Port The Centronics port is a parallel connector for printers that are compatible with the Centronics interface. High-Speed Port The high-speed port feature is not implemented at this time. Video RAM This is 1 MByte of fast video RAM for storing the display image.
Page 25: Data Flow
How the Oscilloscope Works Data Flow Data Flow The data flow gives you an idea of where the measurements are made on the acquired data, and when the post acquisition signal processing is applied to the data. Figure 1-2 is a data flow diagram of the oscilloscope. The diagram is laid out serially to give you a visual perception of how the data is affected by the oscilloscope.
Page 26 HP-IB bus, or transferring data to and from the disk. Notice that the measurements are performed on the real-time data after it has gone through postprocessing.
Page 27 Also, you may notice that postprocessing the data in the equivalent-time signal path includes calculating functions, storing data to the waveform memories, transferring data over the HP-IB bus, or transferring data to and from the disk. After the measurements are performed, the data is sent through the display portion of the oscilloscope.
Page 28: Sampling Overview
That is why the HP 54713A plug-in has a 500-MHz bandwidth. It uses one slot, and one-fourth of 2 GSa/s is 500 MHz. The HP 54721A plug-in has a bandwidth of about 1 GHz because it uses two slots, and one-fourth of 4 GSa/s is 1 GHz.
Page 29 How the Oscilloscope Works Sampling Overview Figure 1-3 shows a 489-ps pulse sampled at 1 GSa/s. You may notice that there are ten different acquisitions. From the picture in figure 1-3, it is difficult to get a sense of what the signal looks like. Any of the ten traces, or none of them, may represent the signal.
Page 30 How the Oscilloscope Works Sampling Overview Figure 1-4 shows the same 489-ps pulse sampled at 2 GSa/s. Notice that ten acquisitions were taken again. This time you have a better sense of what the signal looks like. However, there are still enough differences among each of the ten waveforms that you can say the signal is undersampled.
Page 31 How the Oscilloscope Works Sampling Overview Figure 1-5 shows the same 489-ps pulse sampled at 4 GSa/s. You cannot tell from the picture, but there are still ten acquisitions. Notice that the oscilloscope now acquires enough data on each acquisition so that it can more faithfully reconstruct the signal.
Page 32 50 MHz. The HP 54711A and HP 54712A plug-ins are best suited for equivalent-time sampling because they allow access to the highest system bandwidths. 1–15...
Page 33 How the Oscilloscope Works Sampling Overview Figure 1-6 shows the same 489-ps pulse as figure 1-4. Because the signal is repetitive, the sampling mode was changed from real time to equivalent time. You may notice how the increased system bandwidth and higher effective sample rate results in excellent reconstruction of the signal.
Page 34: Choosing Plug-Ins
How the Oscilloscope Works Choosing Plug-ins Choosing Plug-ins The accuracy of your measurement results depends on the configuration of your oscilloscope system. Part of the configuration is knowing how to set up the various menus that are described in this book for your application. The rest of the configuration is comprised of choosing the plug-ins and probes to use for the measurement.
Page 35 *The standard 1-2-5 sequence in the 54722A plug-in, which is selected by the mainframe’s front-panel knob, does not correspond exactly to the attenuator ratios in the hardware. Refer to the HP 54722A Attenuator Plug-in User’s Reference for more information about the attenuator ranges.
Page 36 How the Oscilloscope Works Choosing Plug-ins Use the HP 54713B plug-in when: • The signal happens once or infrequently, and you are using the real-time sampling mode. • Your application requires only 500-MHz bandwidth, (rise time is slower than 2.1 ns) and you need more than 2 channels.
Page 37: Choosing Probes
How the Oscilloscope Works Choosing Probes Choosing Probes Two problems arise when you use a probe to connect an oscilloscope to a circuit. First, the probe degrades the circuit under test. The new circuit behaves differently than does the circuit without the probe. The behavior you see is the behavior of the circuit with the probe.
Page 38 How the Oscilloscope Works Choosing Probes Probe Loading Figure 1-8 shows a simplified diagram of the circuit with the probe attached to indicate the principal loading effects. The probe load has both resistive and capacitive components. In addition to this, the inductance in the probe ground lead can cause ringing.
Page 39 How the Oscilloscope Works Choosing Probes The resistance of the probe to ground forms a divider network with the source resistance of the circuit under test. This reduces the signal amplitude and the dc offset. For example, if the probe’s resistance is 9 times the Thevenin output resistance of the circuit under test, the amplitude is reduced by about 10 percent.
Page 40 How the Oscilloscope Works Choosing Probes The capacitance of the probe tip to ground forms an RC circuit with the output resistance of the circuit under test. The time constant of this RC circuit slows the rise time of any transitions, increases the slew rate, and introduces delay in the actual time of transitions.
Page 41 How the Oscilloscope Works Choosing Probes Perhaps you have connected an oscilloscope to a circuit for troubleshooting only to have the circuit operate correctly after connecting the probes. The capacitive loading of the probes can attenuate a glitch, remove ringing or overshoot, or slow an edge just enough that a setup or hold time violation no longer occurs.
Page 42: System Bandwidth
How the Oscilloscope Works System Bandwidth System Bandwidth The bandwidth of the combined oscilloscope and probe system must be sufficient to accurately reproduce the input signal. Otherwise, time-interval measurements are inaccurate. For example, if the oscilloscope and probe have a combined rise time of 1 ns, and the signal also has a 1-ns rise time, the measured rise time is: √...
Page 43 First, there is the low-impedance resistive divider probe, like the HP 54006A. Second, is the compensated, high-resistance passive divider probe, like the HP 10430A. Third, there is the active probe, like the HP 54701A. Resistive Divider Probes Resistive divider probes are designed for oscilloscopes with a 50-Ω...
Page 44 How the Oscilloscope Works System Bandwidth Because of the physical geometry of this type of probe and because the divider does not have to be capacitively compensated, this type of probe has the lowest capacitive loading of any probe. This low capacitance and its inherent wide bandwidth make it best suited for wide bandwidth measurements or those measurements where timing is the most critical parameter.
Page 45 One of the compensating capacitors is made adjustable so you can optimize the step response flatness because the input capacitance of the oscilloscope is unknown. The HP 54720A provides a square wave at the calibrator output for this purpose.
Page 46 How the Oscilloscope Works System Bandwidth Not all 1-MΩ divider probes work with all 1-MΩ oscilloscope inputs. The probe data sheet shows the range of oscilloscope input capacitance it can accommodate. You must make sure that the input capacitance of the oscilloscope is within that range.
Page 47 System Bandwidth Active Probes An active probe, like the HP 54701A, has a buffer amplifier at the tip. See figure 1-14. This buffer amplifier drives a 50-Ω cable terminated in 50 Ω at the oscilloscope input. Active probes offer the best overall combination of...
Page 48 How the Oscilloscope Works System Bandwidth Summary There is no such thing as the perfect probe, so you must use some discretion in choosing the best type of probe for each measurement. To make the correct choice, it’s helpful to know the equivalent circuit of the circuit under test.
Page 49 10 mV/div HP 54713B 500 MHz 10 mV/div HP 54721A 1 GHz 10 mV/div HP 54006A Passive 50-Ω Divider Probe Input resistance 500 Ω (10:1) or 1000 Ω (20:1) Input capacitance Typically 250 fF Division Ratio 10:1 or 20:1 When used with...
Page 50 Autoscale Key 2–3 Clear Display Key 2–3 Display 2–4 Entry Devices 2–7 Fine Mode 2–8 Help Menu 2–9 Indicator Lights 2–10 Local Key 2–12 Run Key 2–13 Stop/Single Key 2–14 Front-Panel Features...
Page 51 Front-Panel Features This chapter describes the display, indicator lights, entry devices, and hardkeys that do not display menus on the screen. Those hardkeys that display menus are described in chapters that follow. Understanding the information in this chapter will help you in operating the oscilloscope.
Page 52: Front-Panel Features Autoscale Key
Front-Panel Features Autoscale Key Autoscale Key The Autoscale key causes the oscilloscope to quickly analyze the signal. Then, it sets up the vertical, horizontal, and trigger to best display that signal. Autoscale can find repetitive signals with a frequency greater than or equal to 50 Hz, a duty cycle greater than one percent, and an amplitude of 50 mV p-p or greater.
Page 53: Display
Front-Panel Features Display Display The oscilloscope has a 9-inch, high-resolution, color display. This display is divided up into several areas that are shown in figure 2-1. Status area The status area displays prompts, messages, error messages, warnings, acquisition status, sample rate in the real-time mode, and the number of averages when averaging is turned on in the equivalent-time mode.
Page 54 Front-Panel Features Display Graticule area The graticule area is also referred to as the waveform viewing area. This is where all the waveform data and markers are displayed on the screen. Time base area The time base area lists the time base scale setting, reference location, and position setting.
Page 55 Front-Panel Features Display Marker results and statistics results area The marker results and statistics results share the same area. The statistics results are displayed only when the manual and waveform markers are turned off, or when the measurement marker readout is turned off. Softkey menu area The softkey menus are displayed in this area.
Page 56: Entry Devices
Front-Panel Features Entry Devices Entry Devices The entry devices are the knob, arrow keys, and keypad. You can use the entry devices to change the numeric setting of some softkeys, like trigger level, or to select an item from a list of choices. When you use the entry devices to scroll through a list of choices, you may notice that the background color of each item changes as scroll through the list.
Page 57: Fine Mode
Front-Panel Features Fine Mode Fine Mode The fine mode allows you to change the channel scale, offset, and time base scale in smaller increments using the knob than the knob normally allows. For example, on most plug-ins the knob changes the channel scale in a 1-2-5 sequence, like 100 mV, 200 mV, and 500 mV.
Page 58: Help Menu
Front-Panel Features Help Menu Help Menu The help menu is designed to aid you in finding the initial key sequence to execute a particular feature. When you press the Help key, a three-column index is displayed on the screen. The left column lists the features of the oscilloscope, the middle column lists the hardkey key, and (if needed) the right column lists the softkey you press to find that feature.
Page 59: Indicator Lights
Front-Panel Features Indicator Lights Indicator Lights There are three indicator lights near the top-left corner of the oscilloscope. These lights can give you a quick indication about the acquisition status of the oscilloscope. Armed When the armed light is turned on, it indicates that the trigger circuit is armed and waiting for a valid trigger event to occur.
Page 60 Front-Panel Features Indicator Lights When the oscilloscope is externally triggered, there is no such indicator. However, you can use the triggered light to help you determine the trigger thresholds. To do this, simply move the trigger level in either direction. When the triggered light turns off, you know that is one of the trigger thresholds.
Page 61: Local Key
Front-Panel Features Local Key Local Key You get to the local key by pressing the blue shift key on the keypad, followed by pressing the Stop/Single key. The local key tells the oscilloscope to return control to the front-panel. This is the only active key when the oscilloscope is under remote control.
Page 62: Run Key
Front-Panel Features Run Key Run Key The Run key causes the oscilloscope to resume acquiring data. If the oscilloscope is stopped, it starts acquiring data on the next trigger event. If the oscilloscope is already in the run mode, it continues to acquire data on successive trigger events.
Page 63: Stop/Single Key
Front-Panel Features Stop/Single Key Stop/Single Key Pressing the Stop/Single key causes the oscilloscope to stop acquiring data. The status area of the screen displays the message "Acquisition Stopped." Each subsequent press of the Stop/Single key rearms the trigger circuit. The next trigger event causes the oscilloscope to make a single acquisition, any measurements are recalculated, and the status area of the screen displays the message, "Acquisition Complete."...
Page 64 Front-Panel Features Stop/Single Key To capture a single-shot event 1 Connect the signal to the oscilloscope. 2 Press the Channel key (located on the plug-in). Set the channel Display to on. Then, select the Scale and Offset settings to display the signal vertically.
Page 65 2–16...
Page 66 Sampling Mode 3–4 Digital BW Limit 3–6 Interpolate 3–6 Sampling Rate 3–12 Record Length 3–14 Averaging 3–19 Completion 3–20 Acquisition Menu...
Page 67 Acquisition Menu The acquisition menu allows you to customize the way the oscilloscope acquires the data. Some of your choices are selecting the sampling mode, number of averages, sample rate, and record length. Figure 3–1 Acquisition menu map 3–2...
Page 68 Acquisition Menu When you press the Acquisition hardkey, the sampling mode you select determines which of these two softkey menus is displayed. The menu on the left is for the real time-time sampling mode, while the menu on the right is for the equivalent-time sampling mode. 3–3...
Page 69: Acquisition Menu Sampling Mode
Acquisition Menu Sampling Mode Sampling Mode The two sampling modes are real time and equivalent time. Real time is primarily used on events that occur either once or infrequently. Equivalent time is primarily used on repetitive signals. Real time In the real-time sampling mode, all the data points that make up a waveform come from one trigger event.
Page 70 Acquisition Menu Sampling Mode The maximum sample rate allows you to have the maximum single-shot bandwidth. The real-time sampling mode is intended to capture events that happen either once or infrequently. To accurately display infrequently occurring events, you need to capture and display as much data as possible with a single trigger.
Page 71: Digital Bw Limit
Acquisition Menu Digital BW Limit Digital BW Limit Digital bandwidth limit is a low-pass filter that removes high-frequency noise from the waveform. Digital bandwidth limit reduces the bandwidth of the oscilloscope to the current sample rate divided by 20. Digital bandwidth limit improves the vertical resolution of the oscilloscope by reducing both the noise floor in the oscilloscope and any noise riding on the input signal.
Page 72 Acquisition Menu Interpolate Figure 3–2 Interpolation turned off Figure 3–3 Interpolation turned on 3–7...
Page 73 Acquisition Menu Interpolate Interpolate is different from a display feature called connected dots. Connected dots does a linear interpolation by connecting the data points with a straight line. Because this is a display phenomenon, connected dots has no effect on any measurement results. The measurement results are calculated with the data that is in memory rather than what is on the display.
Page 74 Acquisition Menu Interpolate If the applied signal is clipped, digital oscilloscopes cannot accurately reconstruct the signal. Other oscilloscopes do not always give you an indication that the applied signal is clipped, especially if any filters are also turned on. This oscilloscope has a feature that gives you an indication that the data is clipped by not filtering the clipped portion of the waveform.
Page 75 Acquisition Menu Interpolate Figure 3–5 Applied signal is not clipped Figure 3–6 Applied signal is clipped 3–10...
Page 76 Acquisition Menu Interpolate Figure 3–7 Applied signal is not clipped and bandwidth limit is turned on Figure 3–8 Applied signal is clipped and bandwidth limit is turned on 3–11...
Page 77: Sampling Rate
(using both single-wide plug-ins and a two-wide plug-in). The maximum sampling rate is 2 GSa/s per plug-in slot. A two-wide plug-in, like the HP 54721A, uses two plug-in slots which allows a maximum sampling rate of 4 GSa/s. A four-wide plug-in, like the HP 54722A, uses four plug-in slots which allows a maximum sampling rate of 8 GSa/s.
Page 78 Acquisition Menu Sampling Rate When a single-wide plug-in and a two-wide plug-in are both turned on, both plug-ins sample at the same sample rate up to 2 GSa/s. Above 2 GSa/s, the single-wide plug-in samples at its maximum sample rate of 2 GSa/s while the two-wide plug-in samples at the selected sample rate above 2 GSa/s.
Page 79: Record Length
64K per plug-in slot on the D model mainframes. A two-wide plug-in, like the HP 54721A, uses two plug-in slots which allows a maximum record length of 32K on the A model mainframes, and up to 128K on the D model mainframes.
Page 80 (up to 32K or 128K points with a two-wide plug-in, like the HP 54721A; or up to 64K or 256K points with a four-wide plug-in, like the HP 54722A). Use the knob, arrow keys, or keypad to select a record length.
Page 81 Acquisition Menu Record Length Figure 3-9 shows a 256-point record length, a 50-ns/div time base scale, and a 2-GSa/s sample rate. Notice that the entire waveform record is displayed. The 2-GSa/s sample rate fills up the 256-point waveform record quickly, which increases measurement throughput, but does not leave much data for the oscilloscope to display.
Page 82 Acquisition Menu Record Length Figure 3-10 shows the same 256-point record and a 50-ns/div time base scale. However, the sampling rate was set to automatic, so the oscilloscope picks a sample rate of 500 MSa/s to avoid filling up the waveform record too fast and displaying a waveform like figure 3-9.
Page 83 Acquisition Menu Record Length Figure 3-11 shows how the oscilloscope handles the signal if the sample rate and record length are both in the automatic mode. Because of the time base scale setting, the oscilloscope picks a sample rate and record length that optimizes the throughput of the oscilloscope while still displaying most of the waveform record on the screen.
Page 84: Averaging
Acquisition Menu Averaging Averaging Averaging is available in the equivalent-time sampling mode only. Before updating the display or measurements, the oscilloscope averages the newly acquired data with the existing data. The higher the number of averages, the less impact each new waveform will have on the composite averaged waveform.
Page 85: Completion
Acquisition Menu Completion Completion The Completion control is provided to allow you to make a tradeoff between how often equivalent time waveforms are measured and how much new data is included in the waveform record when a measurement is made. The completion control has no effect in the real-time mode, since the entire waveform record is filled on every trigger.
Page 86: Applications
Applications...
Page 87 Applications Loading Applications Because the application is stored in the oscilloscope’s volatile memory, you must reload the application each time the oscilloscope’s power is cycled. If the scope is turned on. Place the disk into the disk drive. Press the Application key at the bottom of the display. Press the Install Application softkey.
Page 88 Mainframe Calibration 5–3 Plug-in Calibration 5–4 Normal Accuracy Calibration Level 5–5 Best Accuracy Calibration Level 5–6 Probe Calibration 5–8 Calibration Overview...
Page 89 Calibration Overview This section briefly explains the calibration of the HP 54720 and HP 54710 oscilloscopes. It is intended to give you or the calibration lab personnel an understanding of the various calibration levels available, and how they were intended to be used. Also, this section acquaints you with the terms used in this manual, the help screens, and the data sheet as they apply to calibrating the oscilloscope.
Page 90: Calibration Overview
RAM. Mainframe calibration is initiated from the "Utility/Calibrate/Calibrate Mainframe" menu, or from the key on the front panel of the HP 54717A Calibration Plug-in. Mainframe calibration should be done on a periodic basis (at least annually), or if the temperature since the last mainframe calibration has changed more than ±5 °C.
Page 91: Plug-In Calibration
Calibration Overview Plug-in Calibration Plug-in Calibration Plug-in calibration allows the oscilloscope to establish the calibration factors for a particular plug-in independent of the mainframe in which it is calibrated. These calibration factors are stored in the plug-in’s EEPROM, so the factors stay with plug-in, not with the mainframe the plug-in was calibrated in.
Page 92: Normal Accuracy Calibration Level
The intent of this level of calibration is to allow any plug-in to be inserted in any mainframe slot and still achieve a typical vertical accuracy of ±3%. For two-wide plug-ins, like the HP 54721A, the interleaving of the two mainframe slots is performed during the best accuracy calibration.
Page 93: Best Accuracy Calibration Level
Calibration Overview Best Accuracy Calibration Level Best Accuracy Calibration Level Best accuracy calibration level refers to the level of accuracy that is achieved when a plug-in is installed in a mainframe slot and is calibrated to the best accuracy level. A best accuracy calibration is initiated from the "Channel/Calibrate/Calibrate to best accuracy"...
Page 94 Calibration Overview Best Accuracy Calibration Level For the best measurement results, a channel (plug-in/slot combination) should be calibrated to best accuracy level. Also, two wide plug-ins must be calibrated to best accuracy level to give accurate results in real-time mode. The best accuracy calibration level has a temperature ∆...
Page 95: Probe Calibration
±4%. For active probes that the oscilloscope can identify through the probe power connector, like the HP 54701A, the oscilloscope automatically adjusts the vertical scale factors for that channel even if a probe calibration is not performed. For passive probes or nonidentified probes, the oscilloscope adjusts the vertical scale factors only if a probe calibration is performed.
Page 96 Display 6–4 Scale 6–5 Offset 6–6 Input 6–6 Probe 6–7 Calibrate 6–10 Channel Menu...
Page 97 Figure 6-1 is the channel menu map for the HP 54712A Amplifier plug-in. The other plug-ins may have specific features that are not shown on this menu map. The purpose of this menu map is to show you the softkeys that are talked about in this chapter.
Page 98 Channel Menu Figure 6-1 Channel menu and menu map for the HP 54712A plug-in 6–3...
Page 99: Channel Menu Display
Channel Menu Display Display Display turns the channel display off and on. When the channel display is on, a waveform is displayed for that channel, unless the offset is adjusted so that the waveform is clipped off the display. Also, the channel number, vertical scaling, and offset are displayed at the bottom left of the waveform area.
Page 100: Scale
Channel Menu Scale Scale Scale controls the vertical scaling of the waveform. If the fine mode is off, then the knob and arrow keys change the vertical scaling in a sequence that is determined by the hardware scale selections. The hardware scale sequence depends on the plug-in you are using.
Page 101: Offset
Channel Menu Offset Offset Offset moves the waveform vertically. It is similar to the position control on analog oscilloscopes. The advantage of digital offset is that it is always calibrated. The offset voltage is the voltage at the center of the graticule area, and the range of offset depends on the scale setting.
Page 102: Probe
Channel Menu Probe Probe The probe menu allows you to set up the oscilloscope for the probe you are using, and to calibrate the a probe to the probe’s actual attenuation and offset. Atten units Attenuation units let you pick how you want to represent the probe attenuation factor.
Page 103 Channel Menu Probe Units Units lets you select unit of measure that is appended to the channel scale, offset, trigger level, and vertical measurement values. These units are Volt, Ampere, Watt, or unknown. You use Volt for voltage probes, Ampere for current probes, Watt for optical-to-electrical (O/E) converters, and unknown for other units or when you are not sure what the unit of measure is.
Page 104 Channel Menu Probe Example The mainframe’s CAL signal is a voltage source. You cannot use it to Other devices calibrate to the probe tip when units are set to Ampere, Watt, or unknown. Instead, you set the external gain and external offset to compensate for the actual characteristics of your probe or device.
Page 105: Calibrate
If one of the channels you are skewing is a trigger source, skew the other channel to it. If you are skewing probes, connect the probes to the calibrator output on the mainframe using a BNC Tee and probe-tip-to-BNC adapters (HP 10218A). Then, set the calibrator output to 500 kHz. 6–10...
Page 106 Channel Menu Calibrate Calibrate to best accuracy Calibrate to best accuracy allows you to achieve the one percent accuracy specifications. A best accuracy calibration is valid for a specific plug-in, in a specific slot, in a specific mainframe. It is valid as long as the current temperature ∆...
Page 107 Channel Menu Calibrate Cal status Pressing the Cal status (calibration status) softkey displays a screen similar to figure 6-2. Current Date This is the current date and time. You can compare this to the last best accuracy calibration time or the last plug-in calibration time.
Page 108 Channel Menu Calibrate Current Frame ∆Temp This is the temperature change inside the instrument from when the last mainframe calibration was performed. A positive number indicates how many degrees warmer the mainframe is compared to the temperature of the mainframe at the last mainframe calibration.
Page 109 Channel Menu Calibrate Best Accuracy Calibration Memory The oscilloscope displays either protected or unprotected. Protected means that the mainframe memory is write protected so you cannot perform a best accuracy calibration on the plug-in. If you try to perform a best accuracy calibration when the memory is protected, the message "Best Accuracy Calibration Memory Protected"...
Page 110: Define Measure Menu
Thresholds 7–4 Top-Base 7–6 Define ∆time 7–8 Statistics 7–9 Define Measure Menu...
Page 111 Define Measure Menu The define measure menu sets the measurement points (thresholds) where the automatic measurements are made. The menu influences the measurement algorithm by allowing you to use the standard IEEE measurement points, or by allowing you to customize the measurements with the user defined selections.
Page 112 Define Measure Menu Figure 7-2 Define measure menu and menu map 7–3...
Page 113: Thresholds
Define Measure Menu Thresholds Thresholds The Thresholds menu sets the measurement points that the automatic measurements use for calculating the timing measurement results. The threshold points are lower, middle, and upper. For example, rise time is measured from the lower threshold to the upper threshold, while a width measurement is made between two middle thresholds.
Page 114 Define Measure Menu Thresholds User Defined You can set the unit of measure for the upper, middle, and lower thresholds to either % (percent) or Volts. Percent is calculated from the top-base values, and you can set the percent values from −25 percent to +125 percent in 0.1 percent increments.
Page 115: Top-Base
Define Measure Menu Top-Base Top-Base Top-base sets the vertical reference thresholds for amplitude measurements, and the values that the upper, middle, and lower thresholds are calculated from. The top and base softkeys are displayed when user defined is selected. Standard Standard has the oscilloscope calculate the top-base using the IEEE standards and a voltage histogram of the waveform that is on the display.
Page 116 Define Measure Menu Top-Base You can use the markers to give you a visual indication of where you are manually setting the top-base values on a waveform. To use the markers to show the top-base settings 1 Press the Markers key. 2 Select the Measurement mode.
Page 117: Define ∆Time
Define Measure Menu Define ∆time Define ∆time Define ∆time sets up the parameters for all automatic ∆Time measurements. The sources for the ∆time measurement are not selected in this menu. You select the sources when you select automatic ∆Time measurement from the keypad on the front panel (shift milli on the keypad).
Page 118: Statistics
Define Measure Menu Statistics Statistics Statistics calculates the mean and standard deviation and the minimum and maximum of the automatic measurement results. The statistics results are displayed below the lower right portion of the graticule area. This is the same area where the marker results are displayed. If the marker results are displayed instead of the statistics results, either turn off the manual and waveform markers or turn off the readout for the measurement markers.
Page 119 Define Measure Menu Statistics The statistics results are reset or restarted under the following conditions: • Selecting the measurement. • Turning on the display of the signal under measurement. • Changing any of the thresholds in the define measure menu. •...
Page 120 Define Measure Menu Statistics When you press the Statistics softkey, this second-level softkey menu comes up on the display. Stops the statistics measurements, resets the results, and erases the statistics measurement results from the display. mean, stddev Mean and stddev (standard deviation) calculates the mean and standard deviation of the automatic measurement results.
Page 121 Define Measure Menu Statistics Mean is calculated as: ∑ µ ; ( 1 ≤ n ≤ 65,534 ). µ (n−1)+x n− µ ; n = 65,535. µ = mean n = count since last statistics reset x = measurement result Standard deviation is calculated as: −1 ⁄...
Page 122: Disk Menu
Directory 8–3 Load 8–5 Store 8–6 Delete 8–8 Format 8–9 Type 8–10 File Format 8–12 From File, To File or File Name 8–20 To Memory 8–21 Disk Menu...
Page 123 Disk Menu The oscilloscope has a high density, 3-1/2 inch, MS-DOS compatible disk drive. In the disk menu you can save and recall waveforms, save and recall front-panel setups, delete files from a disk, format a disk, or obtain a directory listing of a disk. In other menus you can use the disk drive to load applications, load new system firmware, or save a copy of the display information in a TIFF, GIF, PCX, or printer specific format.
Page 124: Directory
Disk Menu Directory Directory When you select directory from the list of disk operations a screen like figure 8-2 is displayed. Directory gives you a listing of the files on a disk, including file name, type, size, date, time, and the available space left on the disk. When you press the Disk hardkey to enter the disk menu, the oscilloscope checks to see if a disk is in the drive.
Page 125 Disk Menu Directory You can also update the directory listing or get a new directory listing by pressing the Refresh softkey. Use the Refresh softkey when: • You just pressed the Disk hardkey without a disk in the drive. However, there is now a disk in the drive and you want to see a listing of the files on the disk.
Page 126: Load
Disk Menu Load Load Load allows you to select from five file types: waveform, database, pixel memory, setup, or mask. You can bring only these five file types back into the oscilloscope from the disk drive.. When you select a file type, only those files that the oscilloscope recognizes as that file type are listed on the screen.
Page 127: Store
Disk Menu Store Store Store allows you to store waveforms, the database, the pixel memory, front-panel setups, or a mask to the disk. Files are stored to the root directory only, and the appropriate extension is automatically appended to the file name. The file extensions are listed below. •...
Page 128 Disk Menu Store Setup files are about 10 Kbytes in size and pixel files are about 15 Kbytes in size. However, the size of waveform files depends on the type of format, the setup of the oscilloscope, and the waveform source. A blank high-density disk has about 1.44 Mbytes of available space, so you could store about 140 setup files, or about 96 pixel files to a blank disk.
Page 129: Delete
Disk Menu Delete Delete Delete allows you to delete a selected file from the disk. Simply use the knob, arrow keys, or keypad to scroll through the directory listing of the disk. Press the File name softkey to enter a file name. Pressing the File name softkey displays another softkey menu that allows you to enter a file name.
Page 130: Format
Disk Menu Format Format Format allows you to format 3-1/2 inch, high-density disks in the oscilloscope. ® The formatted disks are MS-DOS compatible, and you can use them in other ® disk drives that are also MS-DOS compatible. However, you may notice that there is a faster disk access time when you use disks in the oscilloscope that were formatted by the oscilloscope.
Page 131: Type
Y values. The format you select determines the file extension that is automatically appended to the file name during the store operation In the HP 54710D and 54720D, you can only use the .TXT format on waveforms of 128K points or less. •...
Page 132 Disk Menu Type Database The database type is for storing the database to a disk or for loading a database file from a disk. A database file is stored in the internal format only, and database files have a .WDB file extension. Pixel A pixel memory file has a .PIX file extension.
Page 133: File Format
When a text file is loaded into the oscilloscope, it is placed into one of the four waveform memories by overwriting any data that was previously stored in that waveform memory. In the HP 54710D and 54720D, you can only use the .TXT format on waveforms of 128K points or less. Internal The internal format is a binary file format, which if you try to read it in a word processing program, it will give you meaningless information.
Page 134 Disk Menu File Format Text Verbose The text verbose format is an ASCII file format that uses alphanumeric characters to represent the waveform. You can load text files into a word processing program. Text verbose waveforms have the file extension .TXT. You may notice that text files use about three times more disk space than files stored to a disk using the internal format.
Page 135 Disk Menu File Format If the results are not what you expected after reading an ASCII waveform back into the oscilloscope, the cause is that the oscilloscope is interpreting your data differently than you expected. Try restoring the ASCII waveform from the waveform memory back to the disk.
Page 136 Disk Menu File Format Figure 8-4 Type: versus Points: Count: XInc: 1.70000052347314E+000 XOrg: 1.71799861418549E-001 XRef: YData range: 1.70000E+000 YData center: 1.71800E-001 Coupling: dc 50 Ohms XRange: 1.60000E+000 XOffset: 1.71800002455711E-001 YRange: 1.60000E+000 YOffset: 1.71800E-001 Date: 11 JAN 1993 Time: 14:29:15 Frame: 54720A:3207A00101 Module: 54712A:3207A00112...
Page 137 Disk Menu File Format Type Type describes how the waveform was acquired: normal, raw, interpolate, average, or versus. When this field is read back into the oscilloscopes, all the modes, except versus, are converted to raw. The default value is raw. Points Points indicates the number of data points contained in the waveform record.
Page 138 Disk Menu File Format YRange YRange is the voltage across eight vertical divisions of the display. The default value is 1.60000E-001. YOffset YOffset is the voltage at the center of the display. The default value is 0. Date Date is the date when the waveform was acquired. The default value is 10 AUG 1992 Time Time is the time when the waveform was acquired.
Page 139 Disk Menu File Format Text Y Values Text Y values files are identical to the text verbose files, except the header information is deleted from the front of the file. Figure 8-5 shows an example of the text Y values format. Text Y values files also have a .TXT file extension. Figure 8-5 X Data: 5.657E-001...
Page 140 Disk Menu File Format Mask Formats The mask only format loads the selected mask into the oscilloscope. Loading both the mask and setup is a convenient method to make sure that the scaling for the mask is correct. You would use the mask only selection in cases when you do not want to change the present setup of the oscilloscope.
Page 141: From File, To File, Or File Name
Disk Menu From File, To File, or File Name From File, To File, or File Name The From file, To file, or File name softkey (file field) is used to select a file name for a disk operation. Simply use the knob, arrow keys, or keypad to scroll through the directory listing.
Page 142: To Memory
Disk Menu To Memory To Memory To memory selects one of the four waveform memories you want to load a waveform into. The To memory softkey comes up when you have selected waveform with the Type softkey. The oscilloscope overwrites any data that was previously stored in the waveform memory.
Page 143 8–22...
Page 144 Persistence 9–3 Color Grade 9–5 Draw waveform 9–6 Graticule 9–10 Label 9–14 Color 9–17 Display Menu...
Page 145 Display Menu The display menu controls most of the features that determine how the acquired data is displayed on the screen. You can select the graticule settings, and you can change the color of most of the items that are displayed on the screen. You can also annotate waveforms by using the Label softkey menus to add text to the waveform viewing area.
Page 146: Persistence
Display Menu Persistence Persistence Persistence is a display function that determines how long a data point is kept on the display before the oscilloscope erases it from the display. You can have averaging and persistence on at the same time because when averaging is on, the averaging is done before the data is sent to the display.
Page 147 Display Menu Persistence Gray scaling lets you see how frequently an event is happening. The most frequently occurring events tend to be brighter than less frequently occurring events. Gray scaling is more visible with a low persistence time, about 100 ms to 800 ms, and with dynamic signals. You can use gray scaling on PRBS signals (pseudo random bit sequence) or frequency modulated signals.
Page 148: Display Menu
Display Menu Color Grade Display Color Grade Display The color grade display feature uses the same data base as mask testing and histograms. The data base is the size of the graticule area, which is 256 pixels high by 451 pixels wide. Behind each pixel is a 16-bit counter. Each time a pixel is hit by data, the counter for that pixel is incremented.
Page 149: Draw Waveform
Display Menu Draw Waveform Draw Waveform The Draw waveform softkey determines how the data is displayed. There are three choices for drawing waveforms: fast, connected dots, and high resolution. Fast Fast plots the data points on the display as fast as possible, which gives this mode the fastest throughput.
Page 150 Display Menu Draw Waveform Connected dots Connected dots draws a straight line among the data points on the display. On waveforms where there are only a few dots representing the acquired data points, you may find it easier to have a sense of what the waveform looks like.
Page 151 Display Menu Draw Waveform Figure 9-3 Connected dots instead of interpolation Figure 9-4 Interpolation instead of connected dots 9–8...
Page 152 Display Menu Draw Waveform High resolution The high-resolution mode uses the full resolution of the waveform data to give the best possible representation of the waveform on the display. The high-resolution mode also makes the displayed waveforms look more analog. For example, when averaging is turned on, the waveform data in memory may have a greater vertical resolution than the display.
Page 153: Graticule
Display Menu Graticule Graticule The Graticule softkey menu is shown in figure 9-5. Type Type allows you to select either the grid or frame screen modes. Grid Grid overlays a graticule on the waveform-display area that has ten major horizontal divisions and eight major vertical divisions. There are also tic marks on the axis to indicate minor divisions.
Page 154 Display Menu Graticule Frame Frame displays a border around the waveform-display area with ten major horizontal and eight vertical major divisions marked on the border. Figure 9-6 shows the screen in the frame mode. Use the frame mode when printing to a monochrome printer, so that the graticule lines do not obscure the waveform data.
Page 155 Display Menu Graticule Graphs With one graph, all displayed waveforms are in a single waveform viewing area. With two graphs, the waveform viewing area is divided in half. You can use the Waveform and Location softkeys to position any displayed waveforms in either of the two graphs.
Page 156: Label
Display Menu Label Label The label softkey allows you to annotate waveforms with text. You can place up to 16 labels on the display, and each label can contain up to 64 characters. You can then print the display with the labels to a printer. Remember, labels are not a part of the waveform.
Page 157 Display Menu Label Row The Row softkey allows you to select one of the 19 vertical rows for the placement of the label. Column The Column softkey allows you to select one of the 64 horizontal columns where the label is placed. Label text The Label text softkey brings up a third-level menu.
Page 158 Display Menu Label Modify label The Modify label softkey allows you to either reposition or change the text of an already defined label. Select next label The Select next label softkey allows you to select which label you want to modify. When you enter the menu, the first label you defined is highlighted.
Page 159 Display Menu Label Delete The Delete softkey allows you to delete a label from the display. Select next label The Select next label softkey allows you to select the label you want to delete. When you enter the menu, the first label you defined is highlighted.
Page 160: Color
Display Menu Color Color The color menu allows you to modify the color of most items that are displayed on the screen. Color The Color softkey allows you to choose from the list items. You can use either the knob or arrow keys to scroll through the list. As you scroll through the list, the name of each item and its current color is displayed next to the top softkey.
Page 161 Display Menu Color Trace background The color the waveform viewing area (graticule background). Error The color of error messages. Advisory The color of advisory messages and prompts. Examples of advisory messages are "Storing" and "Setup saved". Status The color of status messages. Examples of status messages are "Acquisition stopped"...
Page 162 Display Menu Color Hue is the gradation of color. You can use the knob, arrow keys, or keypad to vary the hue from 0 to 100. Red is at both 0 and 100, green is at 33, and blue is at 67. Saturation Saturation is the percentage of color that is mixed with white.
Page 163 9–20...
Page 164: Messages
Messages...
Page 165 Messages you may see on your instrument This chapter contains an alphabetical list of messages you may see on the display of your instrument. Only messages needing explanation are contained in this chapter. Other messages that are the result of an action you have taken and explain what the instrument is doing or tell that the action you have requested has occurred are not listed here.
Page 166 This message is displayed as a reminder when a plug-in is installed in a mainframe slot that has no acquisition hardware. For example, slots 3 and 4 of an HP 54710A or 54710D. Busy timeout occurred with plug-in ?: Try reinstalling plug-in The plug-in busy signal was present too long.
Page 167 Execution not possible: ? has no acquisition capability The plug-in indicated by the ? does not have acquisition capability. Select another plug-in that does have acquisition capability. For example, the HP 54718A plug-in only has triggering capability. Function cannot be performed on the selected waveform The function is not defined for this waveform type, and, thus, cannot be performed.
Page 168 Messages Memory error occurred in plug-in ?: Try reinstalling plug-in The checksum or contents of the plug-in’s memory is incorrect. The ? indicates which plug-in has the error. Check the following: Reinstall the plug-in. Finger tighten the knurled screw on the front-panel of the plug-in. If these actions do not solve the problem, there must be a hardware problem in the mainframe or plug-in.
Page 169 Messages Probe attenuation (or gain) exceeds calibration limits The automatic probe cal cannot generate the cal factors to compensate for the gain or attenuation of the probe. The attenuation factor limits are −80 dB to −120 dB.. Setup defaulted This normally occurs when you ask for setup to be defaulted. At power on, the setups are defaulted if a memory error was detected or had occurred prior to power down.
Page 170: Marker Menu
Off 11–3 Manual 11–3 Waveform 11–5 Measurement 11–7 Marker Hints 11–8 Histogram 11–8 Marker Menu...
Page 171 Marker Menu The marker menu allows you to turn on and position colored markers on the display. The default marker color is orange. However, you can change it to a different color in the display menu. You can use the markers to make custom measurements, to use as visual reference points on the display, or to show you where the last automatic measurement was made on the signal.
Page 172: Off
Marker Menu Turns off all of the marker functions, and removes the markers and marker values from the display. The statistics measurement results share the same area of the screen as the marker values. In cases where you turn on statistics, the measurement marker positions hide the statistics measurement results.
Page 173 Marker Menu Manual X1 Position and X2 Position X1 Position moves the X1 marker horizontally, and X2 Position moves the X2 marker horizontally. Use the knob, arrow keys, or keypad to change the marker position. You can make timing measurements with the X markers on the signal. The difference between the marker’s positions is the timing measurement.
Page 174: Waveform
Marker Menu Waveform Waveform There are two waveform markers: + and X. The waveform markers track the waveform data in memory rather than the displayed waveform. Because the waveform data in memory has a much greater resolution than the display, the measurements you make with the waveform markers are much more precise than measurements made with the manual markers.
Page 175 Marker Menu Waveform + Position and X Position The + marker is controlled by the + position and the X marker is controlled by the X position. Use the knob, arrow keys, or keypad to position the markers on the signal. The marker position readouts are displayed near the bottom of the display.
Page 176: Measurement
Marker Menu Measurement Measurement The measurement markers show you where on the signal the last automatic measurement was made. If you make an automatic measurement and the result is already displayed on the screen, then the oscilloscope automatically places the markers when you select them. The markers will stay on the display until you either select a different marker mode, or until you press the Clr meas (clear measurement) key on the keypad.
Page 177: Histogram
Marker Menu Histogram Histogram Histogram displays the histogram markers, which gives you a visual aid as to where the histogram markers are placed on the display. The histogram markers are only displayed when you are in the histogram menu or when you select histogram in the marker menu.
Page 178 Function 12–3 Define Function 12–4 Display 12–7 Math Menu...
Page 179 Math Menu The math menu allows you to define either one or two functions. Each function consists of a math operator and either one or two operands. A function is calculated on data adjusted by the calibration factors, and a new waveform (called a function) is generated by the computation.
Page 180: Math Menu Function
Math Menu Function Function Allows you to select either function one (f1) or function two (f2). You can display both functions on the screen at the same time. Even though a channel display is set to off, you can still use that channel as part of a function and see the results of the function on the display.
Page 181: Define Function
Math Menu Define Function Define Function You can select a math operator for the function, and the waveform source for the operand or operands. Operator The Operator softkey menu is shown at the lower left. You can select any of the 12 math functions as the math operator to act on the operand or operands.
Page 182 Math Menu Define Function Versus Draws a volts versus volts display of the two selected operands. The bandwidth of both the X and Y axis is the full bandwidth of the oscilloscope’s vertical input. Use versus to compare frequency and phase relationships between two signals.
Page 183 Math Menu Define Function Operand The math operator is performed either on operand 1, or on operand 1 and operand 2. The number of operands used depends on the math operator you select. For example, add requires two operands while invert requires only one operand.
Page 184: Display
You can set the scale to track the source waveform or you can adjust the scale manually with the scale and offset keys. In the HP 54710A, 54710D, 54720A, and 54720D, functions are limited to 32K points. On a waveform exceeding this length, functions are calculated on the first 32K points of the waveform.
Page 185 Math Menu Display Function scaling When magnify or versus is the operator, the function scaling softkey replaces the vertical softkey. When you select function scaling, a second level softkey menu allows you to change the vertical and horizontal scaling of the function. Refer to Chapter 21, "FFT Menu,"...
Page 186: Measurements
Measurements...
Page 187 How the Oscilloscope Makes Waveform Measurements This chapter describes the process the oscilloscope uses to make waveform measurements. It also describes the parameters that are measured and how to set up measurements for the best solution. Like any tool, it is important to understand how to use the tool, its limitations, and methods that may overcome some of the shortcomings.
Page 188: The Oscilloscope Waveform Measurement Process
The Oscilloscope Waveform Measurement Process The illustration below shows the basic process used by the oscilloscope when making automatic parametric measurements such as rise time, Vp-p, or frequency. These measurements can be made on input signals, stored waveforms, or functions. In order to start the measurement process, the oscilloscope captures a data record.
Page 189: The Process Starts With Data Collection
Measurements The Process Starts With Data Collection The Process Starts With Data Collection In order to make measurements on a signal, the instrument must first collect data about that signal. In the case of a live signal being measured from the front panel, the measurement process begins as soon as any data is available.
Page 190: Then The System Builds A Histogram
Measurements Then the System Builds a Histogram Then the System Builds a Histogram Once a data record is available, the measurement process builds a histogram of the distribution of the internal voltage levels as shown in figure 13-4. The histogram does not represent the full resolution of the data, however, as this would result in a very large histogram array.
Page 191: The System Calculates Min And Max From The Data Record
Measurements The System Calculates Min and Max From the Data Record The System Calculates Min and Max From the Data Record As it represents the full resolution of the signal, the absolute maximum and minimum voltage levels are determined from the data record. If the waveform is clipped, this information is also recorded.
Page 192: Then It Calculates Top And Base
Measurements Then It Calculates Top and Base Then It Calculates Top and Base The next measurements made are the top and base of the waveform. These measurements come directly from the histogram. The top 40 percent is scanned for the top, and the bottom 40 percent of the histogram is scanned for the base.
Page 193 Measurements Then It Calculates Top and Base The greatest number of data occurrences in the top half of the histogram corresponds to the top. If the occurrence count is less than a predetermined statistically significant value, the top defaults to the value of the absolute maximum.
Page 194: Thresholds Are The Next Values Calculated
Measurements Thresholds Are the Next Values Calculated Thresholds Are the Next Values Calculated Once the top and base are defined, threshold levels used for timing measurements are calculated. These thresholds may be the IEEE values of 10, 50, and 90 percent, or values in percentages or volts that you set. These thresholds are called upper, middle, and lower thresholds in the measurement menu.
Page 195: Finally, Rising And Falling Edges Are Determined
Measurements Finally, Rising and Falling Edges are Determined Finally, Rising and Falling Edges are Determined The final analysis needed to make timing measurements is to define the transition points of the waveform through the threshold levels and to define the rising and falling edges. A rising edge is defined as a transition that passes through the lower, middle, and upper threshold levels.
Page 196 Measurements Finally, Rising and Falling Edges are Determined If there are not enough points on an edge, the rise time measurement, for example, is either not made or is flagged as questionable. The oscilloscope scans the waveform data and records the transitions through the three thresholds.
Page 197 Measurements Finally, Rising and Falling Edges are Determined The oscilloscope defines the points on a rising edge as the last point before crossing the lower threshold to the first point crossing the upper threshold. The points on a falling edge include the last point before crossing the upper threshold to the first point crossing the lower threshold.
Page 198: Standard Waveform Definitions
Standard Waveform Definitions The following definitions of voltage and timing measurements will help you understand just what each measurement consists of. This information might be important in helping you interpret measurement results. Voltage Measurements Once the top and base calculations area completed, most of the voltage measurements can be made.
Page 199 Measurements Voltage Measurements Figure 13–10 Waveform definitions used to make voltage measurements 13–14...
Page 200 Measurements Voltage Measurements Several of the voltage measurements require threshold and edge information before they can be made. • Vavg cycle = average voltage of the first cycle of the signal • Vavg = average voltage of all data on the display •...
Page 201: Timing Definitions
Measurements Timing Definitions Timing Definitions Once the edges and transition points have been defined, timing measurements are made. Timing measurements are made on the first rising or falling edge on the display. • Rise time = time at the upper threshold − time at the lower threshold on the first rising edge •...
Page 202 Measurements Timing Definitions User Defined ∆ Time On the oscilloscope, you may select the threshold level (lower/middle/upper), polarity of edge (either rise or fall), and the edge number. The measurement is then calculated as the time from the first source’s edge to the second source’s edge.
Page 203: Some Important Measurement Considerations
Some Important Measurement Considerations The oscilloscope makes measurements for every trigger, always maintaining continuity between the measurement results and the display. This makes sure that no aberration in the waveform under observation is missed. You may set the markers on the display to track the measurement results.
Page 204: Making Automatic Measurements From The Front Panel
Measurements Making Automatic Measurements from the Front Panel Making Automatic Measurements from the Front Panel The oscilloscope makes its measurements using the data showing on the display. It is therefore important that you correctly window the display to get accurate measurements. Windowing allows you to pick one pulse out of a series of pulses to make measurements on.
Page 205 Measurements Making Automatic Measurements from the Front Panel Pulse Width Measurements A complete positive pulse must be displayed to make a +Width measurement. A complete negative pulse must be displayed to make a −Width measurement. Remember that an edge must pass through all three thresholds to be recognized as an edge.
Page 206: Increasing The Accuracy Of Your Measurements
Increasing the accuracy of your measurements The following information tells you how to obtain the highest accuracy available from the oscilloscope. Though the examples refer to the HP 54720, most of the principles apply to any oscilloscope. The discussion is divided into four sections. The first section describes various methods for making time-interval measurements and the pros and cons of each.
Page 207: Measuring Time Intervals
Measurements Measuring time intervals Measuring time intervals In this section, we discuss measuring a pulse width to show the principles of time-interval measurement. The time interval you want to measure might be a setup time, a propagation delay, or a rise time. However, all time-interval measurements made with oscilloscopes are similar.
Page 208 Measurements Measuring time intervals Automatic Measurements Except in special cases, the simplest and most accurate way to measure the width of a pulse is to use the oscilloscope’s automatic measurement. For the oscilloscope to measure the pulse width automatically, the time/division control must be set so that the entire pulse, including the leading and trailing edges, is on the screen.
Page 209 The double-width plug-in, HP 54721A, gives you twice the memory depth because it uses two of the mainframe’s digitizing channels and associated memory. Therefore, in some situations it is better to use the HP 54721A plug-in for increased memory, though you may not need the higher sampling rate it provides.
Page 210 Measuring time intervals Markers You can measure a time interval manually using the markers in the HP 54720. One advantage of using markers is that you can expand the time base around the start and stop events of the time interval to be measured, thus achieving more time resolution than with automatic measurements (you are not limited by the memory depth).
Page 211: Statistics
Set up the oscilloscope to view a fast-rising edge from a pulse generator, such as an HP 8131A. The triggered edge should be at the center of the screen. Press the Trigger menu key. You will see the trigger level marker displayed on the screen.
Page 212 The faster the slew rate of the source, the easier it is to evaluate jitter. One way to get fast-slewing edges is to trigger a pulse generator, such as an HP 8130A or HP 8131A, with a stable sine-wave source, like an HP 8656B or HP 8657A.
Page 213 Measurements Statistics If the standard deviation of the oscilloscope’s jitter is 1/3 of the standard deviation of the actual jitter, the error in the measured standard deviation will be about 5 percent. Jitter and Averaging Vertical averaging removes the apparent jitter on the display, but may give misleading information about the true behavior of the signal.
Page 214 Measurements Statistics The real-time acquisition mode has an advantage in measuring the true rise time, delay, or other time intervals on jittering signals. In the real-time acquisition mode, a complete record of each transition is acquired on every trigger. The oscilloscope can make accurate measurements on these records and can calculate and display the statistics of measurements on many transitions.
Page 215: Time-Interval Measurements
Measurements Time-interval measurements Time-interval measurements Measuring time intervals with an oscilloscope can be compared to measuring the length of a board with a ruler. However, the signal, unlike the board, is not directly accessible to the senses. Using an oscilloscope is like taking a photograph of the board, then determining the board’s dimensions by measuring the photograph.
Page 216 Random errors that can’t be repeated from measurement to measurement. Figure 13-13 shows how vertical dc errors affect time-interval accuracy. The linearity of the HP 54720 is typically better than 1/2 LSB, so the error is dominated by the offset and gain errors.
Page 217 Measurements Time-interval measurements Time-interval errors due to voltage errors cancel when you measure the time between two edges having the same polarity, amplitude, offset, and slew rate at the same dc level on the same channel. Note that this rule applies only to single-channel measurements.
Page 218 Measurements Time-interval measurements For time-interval measurements between edges of opposite polarity, the errors caused by dc level errors add rather than cancel as shown in figure 13-14. The time errors in locating the leading edge and trailing edge of the pulse reinforce rather than cancel. Figure 13–14 Edges of Opposite Polarity Reinforce dc Errors 13–33...
Page 219 Measurements Time-interval measurements The faster the transition, the smaller the time error introduced by dc level errors. This is true both for edges of the same polarity and for edges of opposite polarity, as well as for channel-to-channel measurements, as illustrated by figure 13-15.
Page 220 Measurements Time-interval measurements Figure 13–16 Measure Time Intervals at Fastest-Changing Part of Transition 13–35...
Page 221 LSB). This time will depend on the vertical resolution and the input slew rate. The vertical resolution of the HP 54720 can vary from 8 bits to more than 10 bits, depending on the plug-in used, the sampling rate, and the sampling mode.
Page 222 See "Probe Capacitive Loading" for more information. At the very high bandwidth of the HP 54720 oscilloscope, the transient response of 50 Ω coaxial cables can be significant. You must use good quality cables and keep them as short as possible for best accuracy.
Page 223 Time-interval measurements Rise Time Response If a step with a Gaussian shape is applied to the input of the HP 54720, the measured 10 percent to 90 percent rise time is approximately equal to the quadrature sum of the rise time of the step and the rise time of the oscilloscope.
Page 224 Table 13-2 shows the error for other ratios of oscilloscope rise time to signal rise time. Table 13-3 shows the approximate error in measuring rise times with various plug-in and probe combinations with the HP 54720. Table 13-2 Rise-Time Measurement Errors...
Page 225 Rise Time Errors for Plug-In and Probe Combinations Actual rise time Plug-In and Probe 500 ps 1 ns 2 ns 3 ns HP 54711A 10.4% 2.7% 0.7% 0.3% HP 54711A and 54006A 10.4% 2.7% 0.7% 0.3% HP 54711A and 54701A 13.8% 3.6% 0.9% 0.4% HP 54712A 18.5% 4.9%...
Page 226 Time-interval measurements Narrow Pulse Response If you apply a narrow pulse to the input of the HP 54720, the waveform is affected in three ways: the height is incorrect, the 50 percent width is incorrect, and the peak is shifted relative to the pulse as shown in figure 13-17.
Page 227 Measurements Time-interval measurements If this pulse is a glitch and you need to know whether it violates the logic threshold, the peak height error might make you believe that it does not. Figure 13-18 shows pulse height error as a function of oscilloscope rise time and input pulse width.
Page 228 Measurements Time-interval measurements You can use the above tables for rise time error to approximate the error in pulse width measurements by substituting "pulse width" for "rise time." If a pulse has Gaussian shape and its width is greater than 3X the oscilloscope’s rise time, the error in the measured pulse width will be less than 5 percent, and the error in peak height measurements will also be less than 5 percent.
Page 229 Measurements Time-interval measurements Probe Capacitive Loading The capacitance of the probe tip to ground forms an RC circuit with the output resistance of the circuit under test. The time constant of this RC circuit will slow the rise time of any transitions, increase the slew rate, and introduce delay in the actual time of transitions.
Page 230 Measurements Time-interval measurements Perhaps you have connected an oscilloscope to a circuit for troubleshooting, only to have the circuit operate correctly after connecting the probes. The capacitive loading of the probes can attenuate a glitch, remove ringing or overshoot, or slow an edge just enough that a setup or hold time violation no longer occurs.
Page 231 Measurements Time-interval measurements Other factors that influence accuracy The HP 54720 can be operated in either real-time or equivalent-time sampling modes. The following discusses the advantages and disadvantages of each mode. Real-Time Sampling In real-time sampling, all the samples are acquired and digitized on every trigger as shown in figure 13-21.
Page 232 Measurements Time-interval measurements Advantages of real-time sampling include the following: • Usable for single-shot measurements • Acquires a complete record of each edge on each trigger. Disadvantages of real-time sampling include the following: • Sampling rate limits the bandwidth • Memory depth limits the time resolution •...
Page 233 In the internal memory of the HP 54720, the full time resolution for each sample is retained, regardless of memory depth. The automatic measurement routines and the waveform tracking markers in the HP 54720 use this high-resolution time data.
Page 234 Bandwidth, Sampling Rate, and Reconstruction The discussion about vertical response told how bandwidth affects time-interval measurement accuracy. In the HP 54720 oscilloscope, like any digitizing oscilloscope, the signal is sampled and then quantized by an A/D converter. In the real-time sampling mode, if the sampling rate is insufficient, information about the input signal will be lost, just as it would be if the bandwidth were insufficient.
Page 235 Measurements Time-interval measurements If you saw only the sampled record, you would conclude that there was no signal. However, if you increase the sampling rate slightly, the picture is very different as shown in figure 13-23. Only one sine wave will fit all the sample points.
Page 236 Measurements Time-interval measurements But what if the signal were not a sine wave? What if it were a square wave, or a triangular wave as shown in figure 13-24. Figure 13–24 Samples Might Represent a Sine Wave of Some Complex Waveform 13–51...
Page 237 Measurements Time-interval measurements Remember that according to Fourier, a square wave or triangular wave is made up of a series of sine waves and contains frequencies higher than the fundamental. If you sample a square wave at a rate equal to four times the fundamental frequency, then reconstruct the samples as a sine wave, you have all the information about the square wave, up to that frequency.
Page 238 A Gaussian filter meets all these requirements, so the response of the HP 54720 and its plug-ins is designed to have an approximately Gaussian response. Figure 13-26 shows the magnitude response of a Gaussian filter in the frequency domain.
Page 239 Measurements Time-interval measurements Figure 13–26 Response of a Gaussian Filter Versus Frequency 13–54...
Page 240 When using the HP 54711A or HP 54712A plug-ins, the bandwidth is greater than 1/4 the sampling rate, so there is risk of aliasing. These plug-ins can be used for single-shot measurements if you know the incoming signal contains no frequencies above 1/4 the sampling rate;...
Page 241 Measurements Time-interval measurements Reconstruction To introduce the concept of reconstruction, let’s return to a familiar example: measuring rise time. If the rise time of the measuring system (oscilloscope and probe) is less than 1/3 the rise time of the signal to be measured, the error in measuring the rise time will be less than 5 percent.
Page 242 Measurements Time-interval measurements What if, as shown in figure 13-28, none of these samples coincide with the 10 percent or 90 percent level? If you use the time between the nearest samples as an estimate of the rise time, the error could be as much as 125 ps, which is 12.5 percent of the actual rise time, and the resolution could not be better than 250 ps.
Page 243 Measurements Time-interval measurements But what if the signal had a glitch between two of the samples as shown in figure 13-29? This glitch contains higher frequency components, and it would not be seen on any oscilloscope with 1-GHz bandwidth, analog or digitizing.
Page 244 Measurements Time-interval measurements Rather than a simple straight line interpolation between sample points, the HP 54720 uses an approximate (sin x)/x digital filter for reconstruction. This yields more accurate time-interval measurements than a simple straight-line interpolation. Filling in between samples in this way is called reconstruction. But is it valid? Does reconstruction add "new"...
Page 245 13–60...
Page 246: Setup Menu
Setup Memory 14–3 Save 14–3 Recall 14–4 Default Setups 14–4 Setup Menu...
Page 247 Setup Menu The setup menu allows you to save and recall up to ten front-panel setups in nonvolatile memories. You can use the setup memories for rapidly recalling setups for production test environments, or when you are comparing waveforms by using more than one setup. You can also set the oscilloscope to its default settings.
Page 248: Setup Menu Setup Memory
Setup Menu Setup Memory Setup Memory Setup memory selects which of the ten nonvolatile memory locations you want to store the front-panel setup to, or recall the front-panel setup from. The setup memories are numbered 0 through 9. Setup memories allow you to easily recall a previous setup for viewing a waveform for further waveform comparison or analysis.
Page 249: Recall
Setup Menu Recall Recall Recall sets up the front panel by recalling a front-panel setup from a selected setup memory. The message "Setup recalled" is displayed at the top-left corner of the screen indicating the setup was recalled. If a setup is recalled and you changed plug-ins, the oscilloscope matches the recalled channel settings as close as possible to capabilities of the new plug-in.
Page 250 Setup Menu Default Setup Acquisition Record length Automatic Digital BW limit Sampling mode Equivalent time Interpolator Averaging Sampling rate Automatic # of averages Display Persistence Variable Intensity Persistence time Minimum Graphs Draw waveforms Fast Channel position All channels upper Graticule Grid Colors Default...
Page 251 Setup Menu Default Setup Channel Display Probe attenuation Unchanged CAL output on HP 54721A plug Scale 1 V/div or maximum Units Volts Offset External offset Sensitivity Default External gain (HP 54711A only) Probe atten units Ratio Input dc 1 MΩ if available or dc 50 Ω...
Page 252: Setup Print Menu
Print Format 15–4 Destination 15–6 Data 15–8 Setup Factors 15–8 TIFF and GIF files on the Apple Macintosh Computer 15–9 Setup Print Menu...
Page 253 Setup Print Menu The oscilloscope can print a copy of the screen to any of several printers or to the disk. It can print to a ThinkJet, PaintJet, LaserJet, DeskJet, or Epson printer. It can also save the printer file, a TIFF file, color TIFF, GIF, or a PCX file to the disk.
Page 254 Setup Print Menu When you press the Setup print hardkey, a menu similar to these menus is displayed. Which menu is displayed depends on the selected print format. The default format is ThinkJet. The PaintJet, LaserJet, DeskJet, and Epson menus are similar to the ThinkJet menu, and the PCX, color TIFF, and GIF menus are similar to the TIFF menu.
Page 255: Print Format
Setup Print Menu Print Format Print Format The print format softkey menu is shown at the left. This menu selects the format the oscilloscope uses to print the screen to the selected destination. The printer formats available are ThinkJet, PaintJet, LaserJet, DeskJet 500C, DeskJet 550C, DeskJet B/W, or Epson.
Page 256 Setup Print Menu Print Format Format The format softkey is displayed when PaintJet is the selected printer. Format allows you to select the type of media, paper length, and background for the PaintJet printout. Paper length There are two paper size choices: English which is 8-1/2-inches by 11-inches, or Metric, which is the A4-size, 210-mm by 297-mm.
Page 257: Destination
Centronics prints to the parallel port on the rear panel of the oscilloscope. HP-IB HP-IB prints to the HP-IB connector on the rear panel of the oscilloscope. When HP-IB is selected, an additional softkey is available that allows you to specify an HP-IB address for the printer.
Page 258 Setup Print Menu Destination If you need to create a file name, press the file name softkey. Then, the softkey menu shown at the left is displayed. With this menu you can create a file name with the letters and numbers from the character list. You can use any of the characters from the character list, and in any order or combination.
Page 259: Data
Setup Print Menu Data Data Data allows you to choose to print just the graticule area, the entire screen, or just the setup factors to a printer or disk. Graticule Graticule prints only the waveform viewing area (graticule area) to the printer or to the disk.
Page 260: Tiff And Gif Files On The Apple Macintosh Computer
Setup Print Menu TIFF and GIF files on the Apple Macintosh Computer TIFF and GIF files on the Apple Macintosh Computer To convert TIFF and GIF files for use on the Apple Macintosh computer. 1 Make sure that the Apple Macintosh computer has a 1.44 Mbyte disk drive, also called "SuperDrive."...
Page 261 15–10...
Page 262: Specifications And Characteristics
Specifications 16–3 Characteristics 16–4 Product Support 16–9 General Characteristics 16–10 Specifications and Characteristics...
Page 263 Specifications and Characteristics This chapter contains the specifications and characteristics for the HP 54710 and HP 54720 that are not dependent upon the plug-in that you are using. The specifications and characteristics for a specific plug-in are in the User’s Reference that is supplied with the plug-in.
Page 264: Specifications
Specifications and Characteristics Specifications Specifications The following are specifications used to test the HP 54700-Series mainframes. Specifications are valid after a 20 minute warm-up period. Time base Time-Interval Measurement Accuracy Real Time ±[(0.2)(sample interval) + 0.007% of delta-time marker reading].
Page 265: Characteristics
ADC with 16,384 point acquisition memory for the HP 54720A and 65,536 points for the HP 54720D. HP 54710A/D mainframe 2, each plug-in slot has its own 2 GSa/s ADC with 16,384 point acquisition memory for the HP 54710A and 65,536 points for the HP 54710D.
Page 266 Specifications and Characteristics Characteristics Trigger Sources All four input plug-in slots can be used for triggering. See plug-in specifications for more details. Edge Slope Positive/negative Holdoff Range 60 ns to 320 ms Pattern Trigger A pattern can be specified using any channel or external trigger input (up to four bits wide).
Page 267 8 GSa/s 16-32,768 4 GHz 244 kHz 1. 2.0 GHz in the HP 54710D and 54720D mainframes 2. 16-32,768 in the HP 54710D and 54720D mainframes 3. 61 kHz in the HP 54710D and 54720D mainframes Span sample rate / 2 Resolution sample rate / record length Frequency Accuracy ±[(0.5 ×...
Page 268 ∆ Magnitude between peaks VMin Minimum amplitude ∆Frequency between peaks Vp-p ∆ Magnitude, Max–Min ∆Mag TMax Frequency at maximum point Vtim Magnitude at a frequency (HP-IB only) FFT Update Time Points Update Time Points Update Time 10 ms 2048 140 ms 15 ms...
Page 269 Characteristics Display Update Maximum Display Update Rate: 550 Kpixels/s HP-IB Transfer Maximum HP-IB Transfer Rate: 500 Kbytes/s Throughput This throughput data was taken in the real-time sampling mode (250 MSa/s) with 512-point records onscreen, no measurements (waveforms/s only), no interpolation, fast draw mode, infinite persistence, markers off, math off, and one channel acquisition.
Page 270: Product Support
HP’s board exchange program assures economical and timely repair of units, reducing the cost-of-ownership. Reliability Under normal use, estimated mean time between failures (MTBF) for the HP 54710A/D is 10,000 hours. The estimated MTBF of the HP 54720A/D is 9,000 hours. 16–9...
Page 271: General Characteristics
Environmental The instruments meet Hewlett-Packard’s environmental specifications Conditions (section 750) for class B-1 products with exceptions as described for temperature and condensation. Contact your local HP field engineer for complete details. Temperature Operating 10°C to +40°C (50°F to +104°F) Non-operating −40°C to +70°C (−40°F to +158°F) Humidity Operating up to 95% relative humidity (non-condensing) at +40°C...
Page 272 33.6 kg (74 lb) Shipping Dimensions Refer to the outline drawings to the right. Notes 1. Dimensions are for general information only. If dimensions are required for building special enclosures, contact your HP field engineer. 2. Dimensions are in millimeters and (inches). 16–11...
Page 273 Specifications and Characteristics General Characteristics Product Regulations IEC 348 Safety UL 1244 CSA Standard C22.2 No.231 (Series M-89) This product meets the requirement of the European Communities (EC) EMC Directive 89/336/EEC. EN55011/CISPR 11 (ISM, Group 1, Class A equipment) Emissions SABS RAA Act No.
Page 274 Scale 17–3 Position 17–3 Reference 17–4 Windowing 17–5 Time Base Menu...
Page 275 Time Base Menu This chapter contains a description of the time base menu and how it controls the horizontal portion of the display. The topics covered are horizontal scale, position, reference, and windowing. Figure 17-1 Time base menu and menu map 17–2...
Page 276: Time Base Menu
Time Base Menu Scale Scale Scale changes the sweep speed from 100 ps/div to 20 s/div. You can change the sweep speed with the knob, keypad, or arrow keys. The knob and arrow keys operate in two modes. One mode is a 1-2-5 step sequence, while the other mode is a fine mode that allows smaller incremental changes.
Page 277: Reference
Time Base Menu Reference Reference Reference places the reference point to the left, center, or right side of the display. The position value is the time of the reference point relative to the trigger event. For example, a position setting of −50 ns indicates that the trigger event occurs 50 ns after the time base reference point.
Page 278: Windowing
Time Base Menu Windowing Windowing When you set the windowing softkey to enabled, the softkey menu at the left is displayed. Windowing is similar to the delayed sweep on analog oscilloscopes because it turns on an expanded time base. This expanded time base allows you to pinpoint and to horizontally expand a portion of the signal for a more detailed or high resolution analysis.
Page 279 Time Base Menu Windowing Window scale Window scale controls the length of the window marker, and the maximum window scale setting is 100% of full screen. The window marker determines how much of the signal is expanded in the window mode. Increasing the window scale decreases the amount of expansion.
Page 280 Trigger Basics 18–4 Sweep 18–6 Mode 18–7 Source 18–20 Level 18–20 Slope 18–20 Holdoff and Conditioning 18–21 Trigger Menu...
Page 281 Trigger Menu This chapter describes the trigger menu, and explains how you can use its controls to trigger the oscilloscope. The trigger circuit performs two functions. It locates the waveform of interest, and it synchronizes the oscilloscope measurement and display to the waveform.
Page 282 Trigger Menu Figure 18-1 Trigger menu and menu map 18–3...
Page 283: Trigger Menu Trigger Basics
Trigger Menu Trigger Basics Trigger Basics A trigger event is defined as an edge of a selected slope (either positive or negative) that transitions through a selected voltage (trigger level). This is referred to as the edge trigger mode. Events leading up to the trigger event are referred to as occurring in negative time, and events that occur after the trigger event are referred to as occurring in positive time.
Page 284 If you have an HP 54711A plug-in installed in the mainframe, it shows up as a trigger source in the edge trigger mode only. Also, trigger 1 on the HP 54722A plug-in shows up as a trigger source in the edge mode. 18–5...
Page 285: Sweep
Trigger Menu Sweep Sweep Sweep lets you select between the triggered and auto sweep modes. Triggered The oscilloscope displays data only after all of the trigger conditions are met. The triggered mode keeps the oscilloscope from triggering and displaying data on the screen before a specific trigger event occurs. Each time the oscilloscope triggers, it lights the Triggered LED.
Page 286: Mode
Trigger Menu Mode Mode Mode lets you select between six trigger modes: edge, glitch, pattern, state, time delay, event delay. Edge is the basic trigger mode. All the other trigger modes are a variation of the edge mode. Edge The edge trigger mode identifies a trigger point by looking for a specified slope and voltage level on a waveform on one channel only.
Page 287 Trigger Menu Mode Glitch Glitch makes it easy to have the oscilloscope look for glitches on a single trigger source. The oscilloscope can distinguish glitches down to 3 ns, and it can capture glitches as narrow as 500 ps. Glitch trigger allows you to trigger on narrow pulses.
Page 288 Trigger Menu Mode Glitch timing requirements For the oscilloscope to trigger on a glitch, the opposite polarity of the glitch must be present for at least 5 ns. The polarity of the glitch is determined by the trigger level. Voltages above the trigger level are of positive polarity, and voltages below the trigger level are of negative polarity.
Page 289 Two-wide plug-ins, like the HP 54721A, take up two slots. For example, if the two-wide plug-in is installed in slots one and two, the channel connector is slot 1 and the external trigger connector is slot 2.
Page 290 Trigger Menu Mode Figure 18-4 shows a two-channel timing diagram, and where the trigger occurs for a few patterns. Also shown is the logic gate equivalent of the each pattern. Figure 18-4 Examples of when a trigger occurs for pattern trigger 18–11...
Page 291 Trigger Menu Mode State State is similar to pattern, except that you select one channel as a clock edge, and you set the remaining channels to define a pattern. Basically state is a selective pattern trigger. The pattern can occur often, but it is checked for validity only on the selected edge on the clock line.
Page 292 Trigger Menu Mode Figure 18-5 shows a three-channel timing diagram. For this example, the clock is a rising edge on channel 3. The oscilloscope was also set to look for when a pattern is present, and the oscilloscope is looking for a high on channels 1 and 2.
Page 293 Trigger Menu Mode Delay time Delay time has the oscilloscope arm on an edge from one of the channel or trigger inputs, wait for a selected period of time, then trigger on an edge from any of the channel or trigger inputs. Basically you can think of delay by time as two edge triggers that are separated by a selectable time.
Page 294 Trigger Menu Mode Figure 18-6 shows a delay-by-time timing diagram. You may notice that the arming event is channel 1, and the trigger event is channel 2. By changing the amount of delay, you can look at various events in a pulse train without the effects of jitter.
Page 295 Trigger Menu Mode Delay events Delay by events has the oscilloscope arm on an edge from one of the channel or trigger inputs, wait for a number of events that you specify in the menu, then trigger on an edge from any of the other channel or trigger inputs. Basically you can think of delay by events as two edge triggers that are separated by a selectable number of events.
Page 296 Trigger Menu Mode Figure 18-7 shows a delay-by-events timing diagram. You may notice that the arming event is channel 1, and the trigger event is channel 2. By changing the number of events, you can consecutively look at pulses in a pulse burst without the effects of jitter.
Page 297 Trigger Menu Mode Standard TV The standard TV menu enables the oscilloscope to trigger on clamped TV signals that use the 525 lines/60 Hz, 625 lines/50 Hz, 875 lines/60 Hz standards. Standard Softkey The standard softkey allows you to select between the three most common TV standards: 525 lines/60 Hz (NTSC) is the standard used in the United States, 625 lines/50 Hz (PAL ) is the standard used in most European and countries, and 875 lines/60 Hz is the...
Page 298 Trigger Menu Mode User Defined TV The user defined TV trigger mode allows for triggering on TV signals that are used in other parts of the world, and for triggering on nonstandard TV signals (like high definition TV). Arm on Softkey The Arm on softkey allows you to set the oscilloscope to trigger on a low or high state.
Page 299: Source
Trigger Menu Source Source When you press Source, a list of the available trigger sources appears on the display. The list of available trigger sources depends on the combination of plug-ins you are using. A plug-in can have internal trigger only, external trigger only, or a combination of both internal and external triggering.
Page 300: Holdoff And Conditioning
Trigger Menu Holdoff and Conditioning Holdoff and Conditioning Holdoff and conditioning allows you to select a trigger holdoff value, and the amount of trigger hysteresis that best fits your application. Hysteresis Hysteresis sets a threshold band that the trigger signal must cross before it is considered a valid trigger by the oscilloscope.
Page 301 Trigger Menu Holdoff and Conditioning Holdoff After the oscilloscope triggers, it waits an amount of time set by holdoff before rearming the trigger circuit. When the trigger circuit is rearmed, it can then accept the next trigger. You can specify an amount of holdoff from 60 ns to 320 ms.
Page 302: Utility Menu
HP-IB Setup 19–3 System Configuration 19–4 Calibrate 19–10 Self-test 19–14 Firmware Support 19–14 Service 19–16 Utility Menu...
Page 303 Utility Menu The utility menu allows you access to these six additional softkey menus: HP-IB setup, System configuration, Calibrate, Self test, Firmware support, and Service. Figure 19-1 Utility menu and menu map 19–2...
Page 304: Utility Menu Hp-Ib Setup
The HP-IB setup menu lets you select an address from 0 to 31. The address number you select is the address that a computer or controller uses to communicate with the oscilloscope.
Page 305: System Configuration
Utility Menu System Configuration System Configuration When you press the System config softkey, a screen similar to figure 19-2 is displayed.’ The system configuration menu gives you information about the mainframe and plug-ins. It allows you to set the date and time on the clock inside the mainframe.
Page 306 Power On Test Indicates if the power-on self-tests passed or failed. These power-on tests verify that the six boards are in the mainframe (five boards in the HP 54710 mainframe). A "Failed" message indicates that at least one board is loose or defective. The power-up routine is kept simple to enable the oscilloscope to power up quickly.
Page 307 Utility Menu System Configuration Boot Revision Indicates the boot ROM version in the mainframe. The boot ROM uncompresses files and loads new system firmware from the disk drive. Slot Indicates the slot that each board is installed in. Power Statistics Total on time (Power on) The time that the oscilloscope has been turned on since it was manufactured.
Page 308 Utility Menu System Configuration Plug-in The information within the box titled "Plug-in" is the configuration of the plug-ins. Slot Indicates the slot that the plug-in is installed in. Model Indicates the model number of the plug-in. If there is no plug-in in a slot, the model number is listed as empty.
Page 309 It also places a date and time stamp on files stored to the disk drive, on waveforms transferred over the HP-IB bus, and on waveforms that are printed. A printed waveform has both the time it was acquired and the time it was printed listed on the printout.
Page 310 Utility Menu System Configuration The oscilloscope remains declassified until a key is pressed, an HP-IB command is sent over the bus, a plug-in is changed, or the power is cycled. When the oscilloscope declassifies the memory in the mainframe, the following actions are performed: •...
Page 311: Calibrate
Utility Menu Calibrate Calibrate Calibrate plug-in The Calibrate plug-in softkey is for performing service work on the oscilloscope. Refer to the Service Guide supplied with the oscilloscope for details on the features for this key. Calibrate frame The Calibrate frame softkey is for performing service work on the oscilloscope.
Page 312 Utility Menu Calibrate Figure 19-3 Calibration Memory This is the status of the Frame cal switch on the rear panel. This switch is normally set to the protected position; before performing a mainframe calibration, set the switch to the unprotected position.
Page 313 Utility Menu Calibrate Slot Indicates the slot that each plug-in is installed in. Model Indicates the model number of the plug-in. If a plug-in is not installed in a slot, the model number is listed as empty for that slot. If the mainframe cannot recognize a plug-in, "~known"...
Page 314 Utility Menu Calibrate Normal indicates that the plug-in is not calibrated for best accuracy. Either the best accuracy calibration factors were cleared from the memory in the mainframe, or that a best accuracy calibration has not yet been performed on this plug-in in this slot.
Page 315: Self-Test
Utility Menu Self-Test Self-Test The Self-test menu is for performing service work on the oscilloscope. Refer to the Service Guide supplied with the oscilloscope for details about this menu. Firmware Support When you press the Firmware support key, a screen similar to figure 19-4 is displayed.
Page 316 Utility Menu Firmware Support Print problem report The problem report is used in case you encounter a problem using this oscilloscope. Complete the problem report and mail or FAX it to Hewlett-Packard. You can print out a problem report by simply connecting a printer to the oscilloscope, selecting printer in the Setup print menu, then pressing the Print problem report softkey.
Page 317: Service
Utility Menu Service Service The Service menu is for performing service work on the oscilloscope. Refer to the Service Guide supplied with the oscilloscope for details on the features in this menu. 19–16...
Page 318 Plug-in 3 model number______________________ Serial number __________________________________ Plug-in 4 model number______________________ Serial number __________________________________ How would you prefer to be contacted? ________ Mail __________Fax __________ Phone Who is your local HP sales representative? _____________________________________________________ Return this form to Hewlett-Packard Hewlett-Packard Company...
Page 319 19–18...
Page 320 HP 54700-Series Oscilloscope Firmware Request Form Please complete this form and FAX or MAIL it to Hewlett-Packard to ensure that HP can contact you when firmware upgrades or new product information becomes available. If you have already signed up for the firmware notification service (option +NA0) for this product, you are already registered and you do not need to fill out this form.
Page 321 Optional Information What are the most critical decisions that this oscilloscope will help you make? ______________________ _________________________________________________________________________________________ _________________________________________________________________________________________ _________________________________________________________________________________________ What critical information do you need from the oscilloscope to make these decisions? ________________ _________________________________________________________________________________________ _________________________________________________________________________________________ _________________________________________________________________________________________ With the built-in disk drive and flash EEPROM memory, it is possible to customize this oscilloscope to specific applications.
Page 322 Waveform 20–3 Pixel 20–6 Waveform Menu...
Page 323 Waveform Menu The waveform menu allows you to save or recall a waveform to a waveform memory or to the pixel memory. When you recall a waveform from a waveform memory or the pixel memory, it is displayed in the default color blue. However, you can change the default color in the display menu.
Page 324 Waveform Menu Waveform Waveform Waveform allows you to store waveforms to one of the four nonvolatile memories in the oscilloscope. Each waveform memory can hold up to 64K points. Because some plug-ins can use more than one slot, it is possible that a waveform can be longer than 64K points on a D model mainframe.
Page 325: Waveform Menu Waveform
Waveform Menu Waveform Memory scaling... The Memory scaling softkey allows you to rescale a waveform vertically and horizontally to make waveform comparison or analysis easier. The To memory softkey selects which memory you want to rescale. You turn on a memory with the Display softkey, and when a memory is on, the Memory scaling softkey is displayed.
Page 326 Waveform Menu Waveform To memory To memory selects which of the available memory locations the oscilloscope saves the waveform to. Pressing the To memory softkey toggles among the nonvolatile memory locations. If the waveform takes up more than 64K on a D model mainframe, the memories are paired or grouped together.
Page 327: Pixel
Waveform Menu Pixel Pixel There is one pixel memory, but you can save several waveforms to that pixel memory. Saving to the pixel memory is like taking a picture of the graticule area. It is a bitmap of the graticule area, and the horizontal and vertical parameters are not saved.
Page 328 Display 21-3 Source 21-3 Window 21-3 FFT Scaling 21-4 FFTs and Automatic Measurements 21-8 FFT Basics 21-10 FFT Menu...
Page 329 FFT Menu Oscilloscopes display signals in the time domain. When an FFT, or fast Fourier transform is added to an oscilloscope, signals can also be displayed in the frequency domain. The frequency domain allows you to see the frequency content of a signal. FFT functionality added to an oscilloscope allows you to analyze a signal from two different, but complimentary points of view, the frequency domain and the time domain.
Page 330: Fft Menu
FFT Menu Display Display The Display softkey turns the FFT function on and off. When on, the FFT Scaling softkey is displayed and a new waveform is displayed on the screen corresponding to the FFT function. This FFT waveform is displayed in the same color used to represent waveforms on slot 3, and the default color is purple.
Page 331: Fft Scaling
FFT Menu FFT Scaling FFT Scaling The FFT Scaling softkey is displayed when the FFT Display softkey is set to on. Pressing the FFT Scaling softkey brings up either of the two following softkey menus. The setting of the Magnify softkey determines which of the two menus is displayed.
Page 332 FFT Menu FFT Scaling Magnify The magnify softkey allows you to zoom in on a portion of the FFT record. Use off to view the entire FFT spectrum, and use on to view a portion of the spectrum. The magnify softkey affects which two keys are displayed below it. When magnify is off, the Span and Resolution softkeys are displayed.
Page 333 FFT Menu FFT Scaling When the resolution is changed, the record length is set to a value that is a power of 2. The FFT operates on the data points that are displayed on the screen. If you have not changed the resolution or span, the number of data points on the screen may not be a power of two.
Page 334 FFT Menu FFT Scaling Magnify span The Magnify span softkey is displayed when Magnify is set to on. The Magnify span softkey uses software expansion to zoom in on the FFT record. The range of values is from the unmagnified span value to 1/200th of the unmagnified span in steps of 1, 2, and 5.
Page 335: Ffts And Automatic Measurements
FFT Menu FFTs and Automatic Measurements FFTs and Automatic Measurements You can access the automatic FFT measurements by pressing the More meas (more measurements) key on the keypad. The available FFT measurements are frequency, magnitude, delta frequency, and delta magnitude. You can track the minimum and maximum or mean and standard deviation values of the measurements with the statistics softkey in the Define meas (define measure) menu.
Page 336 FFT Menu FFTs and Automatic Measurements Pk threshold Peak threshold sets the threshold level for peak searches. In order to be considered a peak, a local max in the FFT spectrum must be above the threshold level and must go up and down at least one-eighth of full scale, (one division).
Page 337: Fft Basics
FFT Menu FFT Basics FFT Basics The Fourier series states that any waveform that repeats in time can be represented by a dc term plus a series of cosine and sine waves. The Fourier series was developed in 1807 by the French mathematician, Jean Baptiste Fourier, to solve thermodynamics problems.
Page 338 FFT Menu FFT Basics Figure 21-2 illustrates what an FFT does. An FFT transforms a time record of N samples into a frequency record of N points from 0 Hz to Fs, where Fs is the sample frequency. The resolution or the spacing between the points in the frequency record is Fs/N.
Page 339 FFT Menu FFT Basics Figure 21-3 shows an example. The upper graticule shows a 977 Hz sine wave in the time domain, and the lower graticule shows the same sine wave in the frequency domain. By looking at the Span and Resolution softkeys, you know that the sample rate (Fs) is 1 MSa/s, the number points (N) is 1024, the Resolution (Fs/N) is 977 Hz, and the Span (displayed spectrum or Fs/2) goes from 0 Hz to 500 kHz.
Page 340 FFT Menu FFT Basics Frequency Measurements For best frequency accuracy on peaks 1 In the acquisition menu, set the Sampling mode to real time and set Interpolate to off. 2 In the channel menu, set the Scaling for almost full scale deflection. 3 Set the Span so that the signal of interest is near the horizontal center of the screen (not down at dc), but high enough to avoid aliasing.
Page 341 FFT Menu FFT Basics Amplitude Measurements For best amplitude accuracy on peaks 1 In the channel menu, make sure the source impedance and probe attenuation are set correctly for your application. 2 In the acquisition menu, set the Sampling mode to real time and set Interpolate to off.
Page 342 FFT Menu FFT Basics Computation of dBm The vertical units of the FFT functions are dBm, and 0 dBm is defined as a 1 mW signal. The formula for converting a signal of power P into dBm is: dBm = 10 log   ...
Page 343 FFT Menu FFT Basics Computation of dBV Another common unit of amplitude is dBV. A 0 dBV signal is defined as 1 Vrms signal. You can convert a dBm reading to a dBV reading by subtracting 13 dB.  0.707107 × V ...
Page 344 Test 22-4 Measurement 22-4 Fail When 22-5 Lower Limit 22-7 Upper Limit 22-7 Run Until 22-7 Fail Action 22-9 Limit Test Menu...
Page 345 Limit Test Menu Limit test allows you to automatically compare measurement results with pass or fail limits, without having to use an external controller. Limit test independently tracks up to four measurements, and you can determine the fail action the oscilloscope takes. Figure 22-1 shows a functional view of the limit test.
Page 346 Limit Test Menu Figure 22-2 Limit test menu and menu map 22–3...
Page 347: Limit Test Menu Test
Limit Test Menu Test Test The Test softkey starts the limit test. Off keeps the limit test from running which allows you to set up test parameters before starting the limit test. On starts the limit test running. When the limit test is on, the total number of failed waveforms, the total number of waveforms measured, and the test status are displayed next to the measurement results.
Page 348: Fail When
Limit Test Menu Fail When Fail When The Fail when softkey brings up a second level softkey menu on the display. Fail when allows you to select when the oscilloscope decides that a test has failed, and what to do with invalid measurements. The four choices are fail inside the limits, outside the limits, always fail, or never fail.
Page 349 Limit Test Menu Fail When Never Fail never sets the oscilloscope so that a measurement never fails on a test. Use the fail never mode when you want to observe one measurement but determine a failure from a different measurement. The fail never mode allows you to monitor a measurement without having to set up any fail criteria.
Page 350: Upper Limit
Limit Test Menu Upper Limit Upper Limit The Upper limit softkey sets the upper failure threshold. The units depend on which measurement is selected with the Measurement softkey. Lower Limit The Lower limit softkey sets the lower failure threshold. The units depend on which measurement is selected with the Measurement softkey.
Page 351 Limit Test Menu Run Until Failures Failures runs the limit test until a set number of failures occurs. When failures is selected, another softkey is displayed that allows you to set the number of failures. Use the failures mode when you want the limit test to reach completion after a set number of failures.
Page 352: Fail Action
Limit Test Menu Fail Action Fail Action The Fail action softkey brings up a second level softkey menu on the display. The Fail action menu allows you to specify what the oscilloscope does with the test data after each test fails, or after the limit test is complete. Store summary The summary is a log of the limit test data from failed test results.
Page 353 Limit Test Menu Fail Action The following events reset all the limit test results, which starts a new summary file. • Changing any of the thresholds in the define measure menu. • Changing the time base window, scale, position, reference, or resolution (number of points) •...
Page 354 Limit Test Menu Fail Action Disk Disk stores the summary information to a disk. The store summary menu allows you to specify the first four characters of the file name. The last four characters are reserved for consecutively numbering any subsequent summary files stored to the disk. If you select SUMM as the first four characters of the file name, the file name of the summary file stored to the disk is SUMM0000.SUM.
Page 355 Limit Test Menu Fail Action Store screen Store screen determines what the oscilloscope does to the data on the screen on a failure. The screen data is a pixel dump of the entire screen area. The choices are off, pixel memory, printer, disk. The screen image allows you to see what the display looked like at the time of the failure , but you cannot rescale it later like you can with waveform memories or functions.
Page 356 Limit Test Menu Fail Action Printer Printer sends the image copy of the waveform area to the destination determined by the Store screen menu. The destination can be one of several printers. The printer selection gives you a hardcopy of what the screen looked like at the time of the failure.
Page 357 22–14...
Page 358: Mask Menu
Polygon Masks in the Oscilloscope 24–4 Test 23–6 Scale Mask 23–7 Edit Mask 23–9 Run Until 23–18 Fail Action 23–20 Mask Menu...
Page 359 Mask Menu Mask testing allows you to compare a waveform against a template. Waveforms within the template pass the test, while waveforms outside the template fail the test. Basically a mask is a way of defining portions of the graticule area as failure regions. If any portion of an acquired waveform enters one or more of the failure regions, the mask tests considers that waveform as failing the test.
Page 360 Mask Menu Figure 23–1 Mask menu map 23–3...
Page 361: Polygon Masks In The Oscilloscope
Mask Menu Polygon Masks in the Oscilloscope Polygon Masks in the Oscilloscope The oscilloscope has three features that use a specific data base that uses a different memory area than the waveform record for each channel. The three features that use the data base are histograms, mask testing, and color graded display.
Page 362 Mask Menu Polygon Masks in the Oscilloscope Even if the display is set to show only the most recent acquisition (minimum persistence), the data base keeps track of all pixel hits while the data base is building. Color graded display, mask testing, and histograms all use the same data base, and turning on any one of them starts building the data base.
Page 363: Test
Mask Menu Test Test The Test softkey starts and stops the mask test. Off stops the mask test. If the histogram and color graded display features are also turned off, then turning off the mask test also disables the data base. Off allows you to construct a mask and configure the test options before actually starting the mask test.
Page 364: Scale Mask
Mask Menu Scale mask Scale mask The Scale mask softkey gives you access to a second level menu that allows you to set the scale of the mask. Basically, you are defining the coordinate system for the mask, where the X, Y pairs 0,0 and 1,1 are located. Scale Source The Scale source softkey selects the channel or function that the Y1 and Y2 markers are scaled to.
Page 365 Mask Menu Scale mask X1 Position The X1 Position softkey defines the vertical line where X=0. The X1 marker tracks the X1 position softkey in this menu. Because the X2 marker value is assigned a delta value that is referenced to the X1 marker, you may notice that the X2 marker moves in conjunction with the X1 marker.
Page 366: Edit Mask
Mask Menu Edit Mask Edit Mask The Edit mask softkey gives you access to a second-level menu that allows you to construct or edit a mask using the polygon method. Procedure to Define a Mask The Procedure to define a mask softkey brings up a set of brief instructions on how to construct a mask.
Page 367 Mask Menu Edit Mask Edit polygon The Edit polygon softkey gives you access to a second level menu that allows you to either edit or construct a polygon. Before entering this menu, make sure that you have the correct polygon number selected with the Polygon softkey.
Page 368 Mask Menu Edit Mask To create a polygon 1 Set the coordinate system in the Scale menu. 2 Select a new polygon number with the polygon softkey in the edit mask menu. 3 Press the Edit polygon softkey. 4 Use the X and Y softkeys to position the cursor at the location on the screen where you want to place point number 1.
Page 369 Mask Menu Edit Mask Moving an X or Y value off of the graticule area (value is either minimum or maximum), fixes that point to the edge of the screen. Changing the scaling will not shrink that point unto the screen. For example, the top line of the polygon in figure 23-3 looks like both points are off the screen.
Page 370 Mask Menu Edit Mask Figure 23–3 Figure 23–4 23–13...
Page 371 Mask Menu Edit Mask The mask in figure 23-5 is a telecommunications mask from the disk supplied with this book. You may notice that the test results are listed below the graticule area. Also, figure 23-6 is a listing of the file for the mask in figure 23-6.
Page 372 Mask Menu Edit Mask Figure 23–6 "DS1Eur 2048 kbit/s" Physical/Electrical Characteristics of Hierarchical Digital Interface. (Geneva 1972 : further amended) Recommendation G.703 /*Level1 Peak 2.37V*/ /*Level2 0.00V*/ /*Delta X 244 ns */ /*Top Polygon /* Number of vertices -0.5, /*Top of screen left side */ -0.5, +0.1 -0.0512, +0.5...
Page 373 Mask Menu Edit Mask To edit a polygon 1 Set the coordinate system in the Scale menu. 2 Select the polygon number with the polygon softkey in the edit mask menu. 3 Press the Edit polygon softkey. 4 Press the Point softkey. 5 Use the knob or keypad to select the point on the polygon you wish to edit.
Page 374 Mask Menu Edit Mask Automask The automask softkey gives you access to a third level menu that allows you to construct a mask using the reference waveform method. You can use the automask menu when you know what a good waveform looks like. Then, you can define a tolerance around the good waveform, and test other waveforms to the mask.
Page 375: Run Until
Mask Menu Run Until Run Until The Run until softkey brings up a second-level softkey menu on the display. The Run until menu allows you to specify when the oscilloscope should stop running the mask test. Mode Mode allows you to configure when the mask test should stop. The five choices are run the test forever, run until a set number of failed waveforms occurs, run until a set number of failed samples occurs, run until a set number of waveforms occurs, or run until a set number of samples occurs.
Page 376 Mask Menu Run Until In the real-time acquisition mode, a waveform is acquired with each trigger event. In the real-time acquisition mode, all the data points that make up a waveform are acquired from a single trigger event. If you select 10 waveforms, that is the same as 10 trigger events.
Page 377: Fail Action
Mask Menu Fail Action Fail Action The Fail action softkey brings up a second level softkey menu on the display. The Fail action menu allows you to specify what the oscilloscope does with the test data after each failure of the mask test, or after the mask test is complete.
Page 378 Mask Menu Fail Action The following events reset all the mask test results, which starts a new summary file. • Changing any of the thresholds in the define measure menu. • Changing one of the polygons, mask scaling, or mask source. •...
Page 379 Mask Menu Fail Action Disk Disk stores the summary information to a disk. The store summary menu allows you to specify the first four characters of the file name. The last four characters are reserved for consecutively numbering any subsequent summary files stored to the disk. If you select SUMM as the first four characters of the file name, the file name of the summary file stored to the disk is MSUM0000.SUM.
Page 380 Mask Menu Fail Action Store screen Store screen determines what the oscilloscope does to the data on the screen on a failure. The screen data is a pixel dump of the entire screen area. The choices are off, pixel memory, printer, disk. The screen image allows you to see what the display looked like at the time of the failure , but you cannot rescale it later like you can with waveform memories or functions.
Page 381 Mask Menu Fail Action Printer Printer sends the image copy of the waveform area to the destination determined by the Store screen menu. The destination can be one of several printers. The printer selection gives you a hardcopy of what the screen looked like at the time of the failure. Disk Disk stores a image copy of the waveform area to a disk.
Page 382 Histograms in the Oscilloscope 24–3 Mode 24–6 Axis 24–6 Histogram Window 24–7 Histogram Scale 24–8 Run Until Mode 24–10 Histogram Menu...
Page 383 Histogram Menu A histogram is a probability distribution that shows the distribution of acquired data within a user-definable, histogram window. You can display the histogram either vertically for voltage measurements or horizontally for timing measurements. The two most common uses for histograms are measuring and characterizing noise or jitter on displayed waveforms.
Page 384 Histogram Menu Histograms in the oscilloscope Histograms in the oscilloscope The oscilloscope has three features that use a specific data base. This data base uses a different memory area than the waveform record for each channel. The three features that use the data base are histograms, mask testing, and color graded display.
Page 385: Histogram Menu Histograms In The Oscilloscope
Histogram Menu Histograms in the oscilloscope Color graded display, mask testing, and histograms all use the same data base, and turning on any one of them starts building the data base. Suppose that the data base is building because color graded display is turned on. When mask testing or histograms are turned on, they take advantage of the information already established in the data base as if they had been turned on the entire time.
Page 386 Histogram Menu Histograms in the oscilloscope To enter the histogram menu Press the blue shift key on the keypad, then press the Display hardkey. Figure 24–2 24–5...
Page 387: Mode
Histogram Menu Mode Mode The mode softkey turns the display of the histogram off and on. The off selection turns off the display of the histogram, while waveform turns on the display of the histogram. If the data base for the histogram is not already built (mask testing and color graded display turned off), waveform starts building the data base and the histogram.
Page 388: Histogram Window
Histogram Menu Histogram Window Histogram Window The hist window softkey gives you access to a second-level menu that allows you to select a region of the data base to include in the histogram. Scale Source The Scale source softkey selects the channel or function that the window scale is derived from.
Page 389: Histogram Scale
Histogram Menu Histogram Scale Histogram Scale The hist (histogram) scale softkey gives you access to a second-level menu that allows you to set the scale of the histogram. Scale Type Linear sets the display of the histogram results to the number of hits per division, while logarithmic sets the display of the histogram results to dB.
Page 390 Histogram Menu Histogram Scale Log offset For log scale type, the offset is in decibels at the left edge or lower edge of the display. The histogram is plotted according to the following formula. dB = 20 log   ...
Page 391: Run Until
Histogram Menu Run Until Run Until The run until softkey allows you to determine when the acquisition of data stops. If forever is selected, you must press the stop/single hardkey to stop the acquisition of data. If either waveforms or samples is selected, after the number of waveforms or samples are met, then the acquisition is stopped, as if you had pressed the stop/single hardkey.
Page 392 Glossary Acquisition The process of chapter 5, "Calibration Overview," sampling and digitizing for additional details about the instantaneous values of a continuous calibration levels of the oscilloscope. analog waveform and storing the values in memory. Bit map A two-dimensional array in which each element stores the Acquisition system A state of a corresponding pixel (dot)
Page 393 Glossary Edge triggering The traditional waveform memory making the triggering mode. A trigger event is display appear to have a higher defined as a transitioning edge of a vertical resolution. When a data specified polarity crossing a point lies between two adjacent specified voltage threshold.
Page 394 Glossary Linear interpolation Another Offset Offset moves the waveform term for connected dots. A straight vertically on the display. It is similar line is drawn between two adjacent to the vertical position control on data points. analog oscilloscopes except that it is precisely calibrated.
Page 395 Glossary Plug-in calibration The plug-in signal can be determined exactly calibration allows the oscilloscope to from the sequence of samples. Two establish the calibration factors for a problems exist in the real world to particular plug-in independent of the prevent exact determination of the mainframe in which it is calibrated.
Page 396 Glossary Sample rate The rate at which waveforms on the display at the the acquisition system samples a same time, whereas skew moves waveform. In the real-time mode, all individual waveforms. Skew is samples in a given waveform record typically used for overlaying are taken from one trigger event and waveforms, or eliminating timing are evenly spaced in time at a...
Page 397 (X axis) of to begin storing waveform samples the waveform. On the HP 54720, into the waveform records. The time this point can be either the left side at which the trigger event occurs is...
Page 398 Add to memory softkey,20–6 FFT,16–6 adjustable output range front-panel calibrator,16–8 specifications,16–3 Cal (calibration) status softkey,6–12 general,16–10 to 16–12 adjusted data,1–12 CAL (calibration) table,1–12 HP-IB transfer rate,16–8 Aliasing,13–60, 21–16 Cal status softkey,19–10 instrument reliability,16–9 altitude characteristics,16–10 Calculated softkey,7–6 mainframe,16–4 altitude considerations,16–10 calculations plug-in,1–25...
Page 399 Index conditions default scale softkey,23–8 display update characteristics,16–8 environmental,16–10 Default setup softkey,14–4 Divide softkey,12–4 connected dots,1–17 Define D time softkey,7–8 Done softkey,9–14 Connected dots softkey,9–7 Define function softkey,12–4 Draw waveform softkey,9–6 considerations Define Meas (Measure) menu,13–32 drift,9–4 altitude,16–10 define measure hardkey,7–4 duty cycle defined,13–24 humidity,16–10 define measure menu,7–2...
Page 400 15–6 HP-IB Glitch trigger softkey,18–8 Pixel memory,8–11 hardware,1–13 Graphs softkey,9–12 setup,8–11 HP-IB softkey,15–6 graticule,15–8 summary,22–10 to 22–11 HP-IB softkey menu,19–3 graticule area,2–5 types,8–5, 8–10 HP-IB transfer characteristics,16–8 Graticule softkey,9–10 file format Hue softkey,9–19 gray scaling,9–3 to 9–4 masks,8–19 humidity characteristics,16–10 Grid softkey,9–10...
Page 401 Index Location softkey,9–12 period,13–27 IEEE standard pulse measurement lockout of local command,2–12 pulse width,13–28 thresholds,7–4 Lower softkey,7–4 setting automatic points,7–4 Ignore softkey,22–6 Luminosity softkey,9–19 statistics,13–34 indicator lights,2–10 time interval,13–30 to 13–33, 13–38 to Infinite softkey,9–4 13–39, 13–41, 13–56 infrequent signals,1–18 timing,11–6 Macintosh file conversion,15–9 input coupling,6–6...
Page 402 Index model number (screen message),19–5 period Print error (status message),15–2 Modify label softkey,9–14 to 9–15 defined,13–24 Print firmware request softkey,19–15 More meas (measurement) menu,21–8 measurement,13–27 Print format softkey,15–4 Multiply softkey,12–4 persistence,9–4 Print hardkey,15–2 Persistence softkey,9–3 Print problem report softkey,19–15 phase relationships,12–5 Printer softkey,22–13 pixel printing...
Page 403 Index Readout softkey,11–7 serial number (screen message),19–5 Center freq,21–7 real time Service menu,19–16 Centronics,15–6 acquisition mode,13–37 setup Clear memory,20–6 sampling,13–54 to 13–55 factors,15–8 Clock,18–12 sampling mode,1–11, 1–16, 1–18, 3–4 file,8–7, 8–11 Color,9–17 real-time specifications,16–3 Setup hardkey,14–2 color grade,9–5 Recall softkey,14–4 Setup memory softkey,14–3 Column,9–14 to 9–15 reconstruction of signal sampling,13–64...
Page 404 Polarity,18–8 Triggered,18–6 High resolution,9–9 Polygon,23–9 Type,8–10, 9–10 Holdoff and conditioning,18–21 Position,17–3 Units,6–8 Horizontal,12–8 Print firmware report,19–15 Update system firmware,19–9 HP-IB,15–6 Print format,15–4 Upper,7–4 Hue,9–19 Print problem report,19–15 Upper limit,22–7 Ignore,22–6 Printer,22–13 User defined,7–5 to 7–6 infinite,9–4 Probe atten (attenuation),6–7 Variable,9–3 Input,6–6...
Page 405 Index standard TV trigger,18–18 throughput,3–8, 3–12 standard TV,18–18 Start edge softkey,7–8 TIFF file conversion,15–9 trigger characteristics,16–5 State softkey,18–12 time Trigger hardkey,18–2 state trigger softkey menu,18–12 errors,13–41 trigger interpolator resolution,16–4 statistics printout,15–2 Trigger menu map,18–3 resetting,7–10 time base Trigger softkey,18–14, 18–16 results area,2–6 delay,18–4 triggered,18–5...
Page 406 Index voltage vertical movement,6–6 level,13–13 Waveform hardkey,20–3 volts versus volts,12–5 waveform math menu map,12–2 Vp-p defined,13–21 Waveform menu map,20–2 Vtop defined,13–21 Waveform softkey,9–12, 22–8 waveform testing,23–2 weight of instrument,16–11 When softkey,18–10 warning messages,13–27 Width softkey,18–8 waveform window,17–5 ASCII file data,8–14, 8–16 to 8–18 window marker,17–5 averaging,3–5, 3–19 Window position softkey,17–6...
Page 407 Index – 10...
Page 408: Declaration Of Conformity
1900 Garden of the Gods Road Colorado Springs, CO 80907 U.S.A. declares, that the product Product Name: Digitizing Oscilloscope Model Number(s): HP 54710A/D, 54720A/D Product Option(s): conforms to the following Product Specifications: Safety: IEC 348:1978 / HD 401 S1:1981 UL 1244 CSA-C22.2 No.
Page 410 Type ersetzt werden. (Siehe Kapitel Replace the cathode-ray tube with an identical Ersatzteile für HP-Teilenummern.) CRT only. Refer to the Replacement Parts Section for the proper HP part number. Das Gerät ist in Deutschland zugelassen unter der Nummer: BW/218/86/ROE Number of German License: BW/218/86/ROE...
Page 411 • © Copyright Hewlett- Safety Safety Symbols Service instructions are for Packard Company 1992-1995 trained service personnel. To This apparatus has been avoid dangerous electric designed and tested in All Rights Reserved. shock, do not perform any accordance with IEC Instruction manual symbol: service unless qualified to do Publication 348, Safety...
Page 412 This Hewlett-Packard This is the first edition of the Hewlett-Packard edition and of any changed product has a warranty HP 54710A and 54720A specifically disclaims the pages to that edition. against defects in material Oscilloscope User’s implied warranties of and workmanship for a period Reference.

This manual is also suitable for:

54710d 54720a 54720d

HP 54710A User's Reference Manual

1 How the Oscilloscope Works

2 Front-Panel Features Autoscale Key

3 Acquisition Menu Sampling Mode

4 Applications

5 Calibration Overview

6 Channel Menu Display

7 Define Measure Menu

8 Disk Menu

9 Display Menu

10 Messages

11 Marker Menu

12 Math Menu Function

13 Measurements

14 Setup Menu Setup Memory

15 Setup Print Menu

16 Specifications and Characteristics

17 Time Base Menu

18 Trigger Menu Trigger Basics

19 Utility Menu HP-IB Setup

20 Waveform Menu Waveform

21 FFT Menu

22 Limit Test Menu Test

23 Mask Menu

24 Histogram Menu Histograms in the Oscilloscope

Quick Links

Related Manuals for HP 54710A

Summary of Contents for HP 54710A