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Service Manual 15-inch LCD Monitor R15AAC/AAU (vs15)
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This manual may not, in whole or in part, be respective owners. copied, photocopied, reproduced, translated, or converted to any electronic or machine readable form without prior written permission of LiteOn Technology Corp. HP HPD_R15AAC/AAU(vs15) Service Manual. Printed in Taiwan.
R15AAC/AAU (vs15) 1) Power Board Operation Therory Therory of Power Board Operation ----------------------------------------------------------------------------------------- 4 2) Inverter Circuit Inverter Circuit ----------------------------------------------------------------------------------------------------------------- 5 3) Interface Operation 3.1 Top --------------------------------------------------------------------------------------------------------------------------- 6 3.2 Power ------------------------------------------------------------------------------------------------------------------------ 6 3.3 VGA & DDC interface ----------------------------------------------------------------------------------------------------- 6 3.4 Scaler GM5321 ------------------------------------------------------------------------------------------------------------- 7 3.5 Key &...
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R15AAC/AAU (vs15) Checking the interface circuit of sync signal ---------------------------------------------------------------------------- 22 9.1 Checking the control circuit of horizontal sync pulse for VGA -------------------------------------------------- 22 9.2 Checking the control circuit of vertical sync pulse VGA ---------------------------------------------------------- 22 10. Checking the resolution change IC movement -------------------------------------------------------------------------- 23 11.
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R15AAC/AAU (vs15) 1). Power Board Operation Therory 1.1 Line filter consists of C801, T801, C802, C803, C804, C809, C815, C838, R801. It eliminates high frequency interference to meet EMI’s requirement. 1.2 Rec & Filter Bridge diode D801 converts AC source into pulsed DC. This pulsed DC is smoothed and filtered by C805. R802 is an NTC ( negative thermal coefficient ) resistor, used to reduce inrush current to be within safe range.
R15AAC/AAU (vs15) 2) Inverter Circuit This unit operates on an output voltage of 21.5V from power source. VDD: R105 get a +5VDC for I101 power supply. Control IC: I101 (OZ9930) 2.2.1 Enable : When pin 1 of I101 is over 0.55V, I101 works. If it is under 0.55V, I101 turns off.
R15AAC/AAU (vs15) Scaler gm2621 (Circuit diagrams sheet 5 of 7) The I307 gm2621 is all-in-one LCD monitor controller. The gm2621 leverages Genesis patented advanced image-processing technology as well as a proven integrated ADC/PLL. Gm2621 also integrates a micro-controller, an OSD controller, and dual LVDS.
R15AAC/AAU (vs15) Key & Panel interface (Circuit diagrams sheet 6of 7) 3.5.1 P306 connector It is LVDS bus, it is from I307 scaler to LCD panel module. The output voltage is 3.3V. 3.5.2 P307 connector The P307 has support keypad function. Control is give effect to for the push switch to be used when the user changes the parameters, in order to modify the respective setting values.
R15AAC/AAU (vs15) Audio (Circuit diagrams sheet 7 of 7) 3.6.1 P307 connector The P307 is audio signal input from the keypad function board. 3.6.2 P308 connector The P308 have two audio function signals. One is audio volume control from the keypad function board.
R15AAC/AAU (vs15) Others 3.7.1 Detection of POWER switch status The I307 gm2621 identifies the ON status of the two power supplies. The identification is made when the power supply is turn off. For example, if the power supply is turn off with the POWER switch, the POWER switch must be turn on when active the power supply again.
R15AAC/AAU (vs15) 3.7.3 List of I/O Pin Assignments of the I311 Pin No. Port Signal Name Initial Function Setting GPIO0 LED_B LED green enable GPIO1 LED_A LED amber enable GPO4 BKLT_ADJ Backlight brightness control GPO2 MUTE Mute Audio GPO3 AUDIO_PW...
R15AAC/AAU (vs15) Trouble shooting For Power Board Check output voltage +5V, +12V, +21.5V are right or not It is not power board problem Check power switch is turn on or not Turn switch on Check power cord (P801), signal cable (P302), P802, P101, P102, P103,...
R15AAC/AAU (vs15) For Inverter Circuit on Power Board Check C102 pin is around 5V. On/Off pin of P802 is over 2V. Brightness pin is between 0V and 3.5V/ It is not inverter problem Check pin6 of I101 is 5V Check R105, C102 and repair them. Check printed wire.
R15AAC/AAU (vs15) No display of screen (Screen is black, color of LED is amber) Does OSM display when you push PROCEED buttom. Proceed "No OSM display" section. When a sugnal isn't being inputed, it is indicated with "VIDEO INPUT". it is indicated with "OUT OIF RANGE"...
R15AAC/AAU (vs15) Nothing displays on screen (Screen is black, color of LED is green) Is backlight lit? Refer "Checking the backlight unit" section" Check the video cable for failure. Check the host for output signal with Does computer output RGB video signals? all black only.
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R15AAC/AAU (vs15) Continue Check the 5V power are supplied on P306 pin 1, 2, 3 (to the LCD panel) Check if theVoltage on I304 pin2 that is DC power at 3.3V. Failure Point 1) I304 failure Check if the TTL level on I301 pin1 that TTL level is low (0~0.8V).
R15AAC/AAU (vs15) Checking the back light unit Is +12V supplied to inverter PWB ? (by the power board) Failure Point 1) Inverter cable disconnection. 2) Power board failure. Check the BKLT_EN signal of the rectangle input P302 pin 6 at TTL high level.
R15AAC/AAU (vs15) Abnormal screen 6.1 Abnormal screen for VGA source Check the R, G, B video signal from computer input on P302 of video connector. Failure Point 1) No R, G, B video signals output from host computer, check computer.
R15AAC/AAU (vs15) Abnormal OSM display adjust problem Check the input DC voltage level whether was changed when pressed function keys on the P307 pin 8, 9. (normal is low level, when push buttom, generated a DC level plus) (Refer table 1) Failure Point 1) Function key wire disconnection.
R15AAC/AAU (vs15) Abnormal plug and play operation Abnormal plug and play operation for VGA Confirm the host computersupplies DDC2 mode. Failure Point The host machine is not communicatiog in DDC2 mode. Check the voltage on P302 pin9 that is power DC 5 V.
R15AAC/AAU (vs15) Checking the interface circuit of sync signal 9.1 Checking the control circuit of horizontal sync pluse for VGA Check the horizontal sync signal on P302 pin13 TTL level. Failure Point VGA Video cable is failure. Check the horizontal sync signal on I307 pin189 TTL level.
R15AAC/AAU (vs15) 11. Audio no signal output Check the audio signal input from the audio source. Failure Point 1) No audio signal from the audio source. 2) Audio cable is failure. Check audio signal input of the I312 TDA7496SA pin5 .
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R15AAC/AAU (vs15) Continue Check I312 pin10 Mute if is high level. Failure Point 1) Printed wire broke between I307 pin57 and Q309and I312 pin10. 2) R383, R384, R385, R338, C393 are open or short. 3) Q312 is filure. 4) I307 is failure.
R15AAC/AAU (vs15) 5) Spare Parts Recommended Parts List Note: 1. The components identified by “ “ mark are critical for X-ray safety. Replace these with only the same parts specified. There is only OTP IC at the model beginning (FPR stage or before). When it put in mass production and there must be Mask coming out.
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Allen Lai R15AAX SCHEMATIC REV 02 PTB-1579 Nov 22 2004 ROAD MAP DESCRIPTION SHEET NO. TITLE SHEET POWER VGA & DDC INTERFACE SCALER GM5621 KEY & PANEL INTERFACE AUDIO REVISION HISTORY REV. DESCRIPTION LAST UPDATE BASED ON PTB-1551 Rev.0C SCHEMATICE FOR LITEON Oct 05 '04 Revrsion change Allen Lai...