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Circuit Description and Troubleshooting: Models: CDP-CX235 CDP-CX270 CDP-CX335 CDP-CX400 CDP-CX450 Prepared by: National Training Department Sony Service Company A Division of Sony Electronics Inc. Course presented by _____________________________________ Date ___________________________________________________ Student Name ___________________________________________...
Table of Contents Overall Block Diagram Tray Table Motor Drive CD Location & Label Storage Information Gathering CD Playback Disc Loading Drive Power Supply / Display Operation Power Supply Motor Stop Optical Pickup Fluorescent Display Power On The Laser and Lens Focus Coil AC Power Only Tracking Coil...
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Spindle Servo APPENDIX Audio / Display Output Control A Communications for Additional Features Analog Audio Output Defective Discs Digital Output Troubleshooting Using the RFO Waveform Display Abbreviations Used in Compact Disc Player Troubleshooting Disc Doesn’t Spin Servo Processing Diagram Focus Disc Won’t Spin Flowchart Disc Spins, But Doesn’t Read the Disc’s Table of Contents (TOC)
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Model Disc List Capacity Price Cd Mech BD Board List Price Optical Assembly / Part number List Price All of these numbers sub to 8-848-379-31 2000 CDP-CX235 170.00 CDM-40B A4724029A $76.15 KSS-213BNK / 8-848-379-31 82.12 CDP-CX270 $1,000 CDM-40B A4699163A $112.01 KSS-213B / 8-848-376-01 82.12...
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Model CDP-CX235 Introduction The board layout of the CDP-CX235 is shown. The bulk of the electronics are on the rear main board. To its left in the vacant area is the CD mecha- This training manual is based upon the model CDP-CX235 CD Changer.
Once Syscon IC501 is confident the tray table information is valid, IC501 Overall Block Diagram turns the CD Changer control over to the user by accepting pushbutton commands. At the core of the 200 disc CD Changer is the System Control (Syscon) The user can use the front panel controls to select another disc or play IC501.
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-13.5V SOURCE FL DISPLAY TUBE DISC DOOR +5V SOURCE DRIVER DISPLAY BD. LIGHT D+5V POWER IC506REG TO BD BOARD SUPPLY RESET AUDIO +11.5V MUTE SOURCE -28V FILAMENT SOURCE VOLTAGE TO DISPLAY BD. OVERALL BLOCK DIAGRAM (MODEL CDP-CX235) 0A122 1251 7/5/00...
The positive output of the bridge rectifier is filtered by C501 to become the Power Supply / Display +11.5V source voltage. The negative output of the bridge rectifier is filtered by C502 to become Overview the –13.5V source voltage. The power supply stage produces seven voltages when the CD Changer +5Volt Source is plugged into AC.
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REGULATOR, 3300 GRIDS 1-15 IC503 MOTOR DRIVER MAIN BD. IC702 FRONT -13.5V SOURCE TO: MUTE DATA, C502 PANEL LED DRIVER TRANSISTORS Q325,Q327, CLK FROM 1000 M66310FP LED’s Q425 AND IC503 MOTOR DRIVER SYSCON IC501 POWER SUPPLY (CDP-CX235) 1A122 1238 7/7/00...
When the output of IC505 is LOW, these microprocessors are held in Grid & Plate Array reset and are inactive (apparently dead). Within the FL tube there are 16 grid structures, each containing 36 plates. Each grid structure produces a character or number by luminating a com- 3.7Vac bination of plates.
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REGULATOR, 3300 GRIDS 1-15 IC503 MOTOR DRIVER MAIN BD. IC702 FRONT -13.5V SOURCE TO: MUTE DATA, C502 PANEL LED DRIVER TRANSISTORS Q325,Q327, CLK FROM 1000 M66310FP LED’s Q425 AND IC503 MOTOR DRIVER SYSCON IC501 POWER SUPPLY (CDP-CX235) 1A122 1238 7/7/00...
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Plate voltage pulses appear only when the CD Changer is powered ON. Plug into AC At power ON, Syscon (IC501 is not shown) sends data to IC701 so it can output these pulses. Positive pulses are output the appropriate plate pins P1-36 to form a number, letter or word when a grid pulse is simultaneously Reset present.
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REGULATOR, 3300 GRIDS 1-15 IC503 MOTOR DRIVER MAIN BD. IC702 FRONT -13.5V SOURCE TO: MUTE DATA, C502 PANEL LED DRIVER TRANSISTORS Q325,Q327, CLK FROM 1000 M66310FP LED’s Q425 AND IC503 MOTOR DRIVER SYSCON IC501 POWER SUPPLY (CDP-CX235) 1A122 1238 7/7/00...
pin 65 to enable regulator IC506. IC506 has three outputs: Power On 1. D+5V from pin 2 is used to: • Power the digital ICs on the DB board; and • Once the CD Changer is plugged into AC, pressing the front panel Power Turn on the LED at the disc door compartment.
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DOOR LUMINATION D+5V IC506 LA5616 SOURCE XRST TO +11.5V C509 BOARD IC101/3, IC102/15 RESET POWER ON MUTE (MAIN BD.) 4.8V Q325,Q327, C511 Q425 MAIN BD. SOURCE TO DRIVER ICSW C508 IC102 (B BD.) 50mVp-p CN501 IC701/PIN X501 FL DATA 10MHz IC701 FL CLK FL DRIVER...
Communications IC501 – IC101 Communications from Syscon to Servo Control IC101 does not occur until the disc is chucked on the spindle motor and ready to play (after the loading motor finishes chucking the disc). This communications is shown below: P M 3 3 9 4 , F L U K E &...
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DOOR LUMINATION D+5V IC506 LA5616 SOURCE XRST TO +11.5V C509 BOARD IC101/3, IC102/15 RESET POWER ON MUTE (MAIN BD.) 4.8V Q325,Q327, C511 Q425 MAIN BD. SOURCE TO DRIVER ICSW C508 IC102 (B BD.) 50mVp-p CN501 IC701/PIN X501 FL DATA 10MHz IC701 FL CLK FL DRIVER...
Syscon IC501 applies an output voltage to pin 23 or pin 24 to drive the motor. The resultant positive or negative voltage is applied to the door The sliding door in the model CDP-CX235 was an improved feature over motor.
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C551 R553 +11.5V R557 (VCC) R552 IC501 D OUT SYSCON OUT 3 CXP84340 IC503 R558 DOOR R551 CXA1291P 1/3 MOTOR BD. DOOR C552 KEY 2 -13.5V (-VCC) R620 D IN R554 R555 R556 M810 CN601/501 Ω Ω 6 10 4 12 S621 C620 OPEN/...
Light Sensors Tray Table Positioning Each light interrupt sensor forms a U channel. At one side of the sensor there is an infrared LED that shines light through the channel. At the In order for the tray table to be positioned, two rows of slots are molded other end is a phototransistor that monitors this light.
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TABLE PHOTO TRANSISTOR LIGHT INTERRUPT (OUTPUT IS SENSOR HIGH WHEN RING 1 LIGHT IS RECEIVED) RING 2 IC801 RING 1 SENSORS ON T.SEN BD. (TOP VIEW) TABLE BOTTOM VIEW IC802 IC803 RING 2 TRAY TOP RING 1 10 SLOTS SLOT SLOTS (MAXIMUM) TRAY TOP...
Direction of Rotation Table Motor Drive The encoder is constructed so its direction from the detent position can be determined by IC501. In the detent position, pin 1 is grounded. In the Syscon IC501 drives the Disc’s Tray Table. IC501 receives information neutral position, pin 3 is grounded.
Tray Table Motor Drive Syscon IC501 drives the motor that rotates the tray table. The following voltages output IC501 and IC503 to move the table in the direction viewed from the top. Tray Table Drive Voltages Table IC501/pin IC503/pin Movement 21 Stop 3.27 0.44...
P M 3 3 9 4 , F L U K E & P H I L I P S CD Allocation & Label Storage Syscon IC501 has its built-in memory to remember if the door was open or closed, whether the disc was chucked or unchucked, and what order of songs to play (program play).
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R522 D521 C522 1F 5.5V R523 CN603/ 1-9, CN501/601 ADDRESS IC701 IC501 DATA IC502 FL DRIVER SYSCON S-RAM MSM9202 CXP84340 MSM5256DFP DATA P1-P36 R524 DISPLAY R521 Q521 DISP. BD. MAIN BD. LUMINOUS BD. D. SEN BD. Q801 DISC=LOW D801 NO DISC=HIGH R804 CN80804/ T.SEN BD.
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segments to display this information on the front panel display tube. P M 3 3 9 4 , F L U K E & P H I L I P S The following waveforms show the data, clock and latch signals from IC501 to IC701 used to produce a display when powered on.
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R522 D521 C522 1F 5.5V R523 CN603/ 1-9, CN501/601 ADDRESS IC701 DATA IC501 IC502 FL DRIVER SYSCON S-RAM MSM9202 CXP84340 MSM5256DFP DATA P1-P36 R524 DISPLAY R521 Q521 DISP. BD. MAIN BD. LUMINOUS BD. D. SEN BD. Q801 DISC=LOW D801 NO DISC=HIGH R804 CN80804/ T.SEN BD.
Motor Stop Disc Loading Drive Just before the cam reaches the end of travel, it toggles the S801 switch on the L. SW Board. The switch grounds IC501/pin 55 or 67 depending The purpose of the Disc Loading Drive stage is to rotate a cam that moves upon the direction of rotation.
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R567 IC503 CXA129IP 3/3 JACK R572 CN509/ IC501 LDOT CN902/808 SYSCON R571 CXP84340 LD OUT LDIN M802 R574 IN SW OUT SW R573 R575 L. MOTOR BD. Ω Ω CN505/806 S801 CAM CW R541 OUT SW. CHUCKED NEUTRAL R542 IN SW. CAM CCW UNCHUCKED L.
Detector Outputs Optical Pickup Laser light striking the information layer of the disc is modulated by the data and returned to the detector area next to the laser diode. Detectors The Optical pick up assembly is the single most complicated device in the A-F receive the light, amplify and output this signal to the external RF CD player.
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FOCAL POINT LASER BEAM LENS TRACKING COIL TRACKING ERROR LASER FOCUS SIGNAL BEAM COIL FOCUS A-D,E,F ERROR DETECTOR LASER SIGNAL OUTPUT CONTROL (FE) OPTICAL PICKUP 7A122 1245 7/7/00...
Sled Motor Servo / Audio Processing Block When the CD Changer is turned ON (no disc chucked), the tray table rotates to determine its position. Within the CD mechanism, the sled In order for the CD player to produce audio, the servo section must con- motor drives the optical assembly toward the spindle motor until the limit trol the laser beam so it can recover the digital data from the disc.
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OPTICAL PICKUP ASSEMBLY RF 0 (EYE PATTERN) ANALOG AUDIO SERVO COIL/MOTOR CONTROL/ DIGITAL DRIVE DIG SIGNAL LOCK PROCESS (DSP) C2PO DISPLAY TUBE DATA DATA (SUB Q) PLATE,GRIDS LOADING SW. S801 (DISC CHUCKED) FL DISPLAY DRIVER USER SYSCON DATA PUSH BUTTONS CLOCK, LATCH LIMIT SW.
search voltage with an amplified FE voltage. The FEO output is sent to a Spindle Motor current driver IC. This IC drives the optical assembly’s focus coil to main- Like the focus serve, the spindle motor servo has two modes of operation. tain focus on the disc during playback.
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OPTICAL PICKUP ASSEMBLY RF 0 (EYE PATTERN) ANALOG AUDIO SERVO COIL/MOTOR CONTROL/ DIGITAL DRIVE DIG SIGNAL LOCK PROCESS (DSP) C2PO DISPLAY TUBE DATA DATA (SUB Q) PLATE,GRIDS LOADING SW. S801 (DISC CHUCKED) FL DISPLAY DRIVER USER SYSCON DATA PUSH BUTTONS CLOCK, LATCH LIMIT SW.
Focus Servo Processing The focus search operation is also initiated when the disc is chucked in the CD Mechanism (S801 not shown) and the limit switch (S101) is closed. There are several main servos that can be tested for normal operation. Servo Control IC101 generates the electrical signal that results in the visible lens movement in the optical assembly.
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D+5V 2.5V DETECTOR OUTPUTS OPTICAL IC103 PICKUP RF AMP KSS-213B CXA2568M Q101 FOCUS TRACK COIL COIL L D ON RIBBON 13,16 14,15 CABLE CONNECTOR CN102 R103 R101 RFDC FOCUS,TRACK SLED DRIVE D+5V IC102 L OUT 1 IC101 DRIVER L,R CH DSP, CLV BA6382FP L OUT 2...
Tracking Servo Defective Tracking Servo Waveforms Channel Signal Name Location The tracking servo is turned on after focus is found (FOK = HIGH). This RFO test point IC103/pin 16 servo results in a periodic track correction signal that looks like about TE test point IC103/pin 13 400mV of noise at the TE test point.
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D+5V 2.5V DETECTOR OUTPUTS OPTICAL IC103 PICKUP RF AMP KSS-213B CXA2568M Q101 FOCUS TRACK COIL COIL L D ON RIBBON 13,16 14,15 CABLE CONNECTOR CN102 R103 R101 RFDC FOCUS,TRACK SLED DRIVE D+5V IC102 L OUT 1 IC101 DRIVER L,R CH DSP, CLV BA6382FP L OUT 2...
The left and right channels of Servo Control IC101 are applied to amplifier IC401. Their outputs are AC coupled to the rear panel phono jacks. The following signal levels were measured using the Sony YEDS-18 test disc track #5 (10kHz mono, 0db).
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IC401 1/2 BA4558 CN101/502 C301 LINE OUT 1 C305 IC101/72 TO AUDIO OUTPUT JACK J904 (JACK BD.) BD BD. R305 R304 IC401 2/2 LINE OUT 2 C405 IC101/75 C401 MUTE RST FROM TRANSISTORS POWER ON Q325 R405 R404 IC506/6 Q327 Q425 DIGITAL OUT DIG OUT TO IC901...
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OPTICAL PICKUP ASSEMBLY RF 0 (EYE PATTERN) ANALOG AUDIO SERVO COIL/MOTOR CONTROL/ DRIVE DIGITAL DIG SOUND LOCK PROCESS (DSP) C2PO DISPLAY DATA TUBE DATA (SUB Q) PLATE,GRIDS USER FL DISPLAY SYSCON PUSH DRIVER DATA BUTTONS CLOCK, LATCH SERVO/AUDIO PROCESS BLOCK 9A122 1251 6/14/00 BD board - Old...
During focus search, the laser power is 0.03mW in Before the disc spins, the sled must be at home position, the laser must this model CDP-CX235 200 disc CD changer. The procedure is: be turned on, and focus must be found. All of these things can be checked easily.
On the main board, connect the “ADJ” test point to ground. In the the disc tray and the luminous sensor as you turn the power on. The CDP-CX235, ADJ is under the large 1-farad capacitor. Ground is the changer will mistakenly sense many discs, attempt to load them and negative lead of the large 1-farad capacitor.
WON’T SPIN REPAIR OR REPLACE CHECK CHECK CHECK DEFECTIVE POWER SYSCON/FL DISPLAY COMPONENT SUPPLY DRIVER CHECK SLED REPAIR REPAIR LIMIT SWITCH P.S. CHECK CHECK SENSORS SPINDLE FOCUS (FOK) SWITCHES CLV MOTOR VOLTAGE SLED DRIVE CHECK REPAIR HIGH PROBABILITY FOCUS LENS FOCUS OF BAD PICK UP MOVEMENT...
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10. Watch your scope as you apply AC power. If the FOK line goes FOK comes from the RFO signal that is derived from the optical detec- HIGH, focus has been found. The transition from search to servo tors A-D. When the RFO reaches a set threshold, FOK goes HIGH is then performed within Servo Control.
P M 3 3 9 4 , F L U K E & P H I L I P S Disc Spins But Doesn’t Read The Disc’s Table Of Contents (TOC) If the disc spins, Servo Control knows the optical assembly is at home position and focus was found (so the laser must be good too).
work before the spindle servo can close. For example, if the tracking servo were defective, the spindle servo loop cannot close because the E, F RF Amp RFO data is unreliable. Therefore the other servos must be checked prior Servo Optical to this check.
No Audio If the disc is spinning and the LOCK test point is HIGH, the servos are working. Audio should output Servo Control if the RF data is valid, and the IC is OK. Servo Control outputs two clues about the audio produced: •...
5. Plug the CD Changer into AC to enter the test mode. Optical Assembly Tests 6. Press the Front panel CHECK button to activate and repeat focus There are three basic checks for the optical assembly. search. An S curve waveform should appear. S Curve Check In this procedure you will check the A-D detectors to see if they are bal- anced with sufficient output level to produce RFO for play.
RFO Level Check Normal The RFO level must be at least 1Vp-p. Tracking Move the scope probe to the RFO test point on the same BD board. error waveform While the disc is playing, the output level should be at least 1Vp-p (spec is 0.5V/div 1.2Vp-p).
Control A is the name given to the Sony bi-directional communications enables you to fade in (start) the next song on the second changer format used in Sony home audio devices. The purpose of the communi- while the current song is fading (out) to an end, thereby mixing the two cation is to automatically perform system functions and provide extra fea- songs at this time.
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the Control A bus. The SIRCS signal is product specific so only the Mini-Disc Tape device the command is designated for will respond, even though all Receiver Recorder Recorder devices receive the command. • No Delay of Playback between CD Changers – The next disc in the programmed (or shuffle) play order will load and pause 30 seconds prior to the current track ends so there is no delay in playback.
Center Hole Misalignment Defective Discs This causes a wobble in the disc and a corresponding bounce in the RF waveform. If the off-center hole is real bad, the disc will not play. Various problems can be found in CDs that cause skipping or clicking sounds (momentary muting) when played.
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Disc Scratches / Black spots (Light scattered / lost) Pit Deformed (poor light cancellation) Focus loss Scratched Disc A scratched disc will scatter some laser light as the laser enters the disc. Since this light will be lost, the RFO voltage will be reduced. If the scratch is small, the lost data is electrically error corrected or predicted in the electronics.
Troubleshooting Using the RFO Waveform RFO during PB of a scratched disc. Notches in the envelope appear on top and sometimes bottom. 1.2Vp-p Time base = 0.5msec/div. Normal RFO (“Eye”) pattern 1.2Vp-p Time base = 0.5usec/div. RFO when the tracking servo is open (defective).
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