ViewSonic Va1912w4 Service Manual

 
 
ViewSonic VA1912w-2  VA1912wb-2 
Model No. VS10866 
19” Color TFT LCD  Display 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
(VA1912w-2_VA1912wb-2_SM Rev. 1b Aug. 2006) 
ViewSonic 381 Brea Canyon Road, Walnut, California 91789 USA - (800) 888-8583 
Service Manual  

ViewSonic Corporation
Copyright 
Copyright © 2006 by ViewSonic Corporation.    All rights reserved.    No part of this publication 
may be reproduced, transmitted, tran scribed, stored in a retrieval system, or translated into any 
language or computer language, in  any form or by any means, electronic, mechanical, magnetic, 
optical, chemical, manual or ot herwise, without the prior written permission of ViewSonic 
Corporation. 
 
Disclaimer 
ViewSonic makes no representations  or warranties, either...

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TABLE OF CONTENTS 
 
 
1.   Precautions and Safety Notices    1
2.  Specification   3
3.  Front Panel Function Control Description  10
4.  Circuit Description  16
5.  Adjustment Procedure  17
6.  Troubleshooting Flow Chart  37
7.  Recommended Spare Parts List  45
8.  Exploded Diagram and Expl oded Parts List  50
9.  Block Diagram  52
10. Schematic Diagrams  53
11. PCB Layout Diagrams  60
 
 
ii
VA1912w-2_VA1912wb-2 
  Confidential - Do Not Copy    

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1. Precautions and Safety Notices 
1 
    Confidential - Do Not Copy   
1. Appropriate  Operation   
  (1) Turn off the product before cleaning.   
  (2) Use only a dry soft cloth when cleaning the LCD panel surface.   
  (3) Use a soft cloth soaked with mild detergent to clean the display housing.   
  (4) Use only a high quality, safety approved AC/DC power cord.    (5) Disconnect the power plug from the AC outlet if the product will not be used for a long period of time.   
(6)...

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Correct methods :  Incorrect Methods : 
Only touch the metal-frame of the panel or the front cover of the monitor. 
Do not touch the surface of the polarizer .  Surface of the panel is pressed by fingers & this may 
cause “ MURA “ 
  
  Take out the monitor with cushion  Take out the monitor by grasping the LCD panel.  That may cause “ MURA“. 
  
Place the monitor on a clean & soft foam pad .  Place the monitor on foreign objects . 
That could scratch the surface of panel 
  
2...

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2. Specification 
2.1 INSTRUCTION   FEATURES  VA1912w-2 / VA1912wb-2 
Size  19” wide 
Luminance (Typ, cd/㎡)  300 cd/㎡ 
Contrast Ratio (Typ)  500:1 
Colors ( 6 bit + 2 bit FRC)  16.2 M colors 
Response Time (Typ)  8 ms 
Viewing Angle  (H/V) 150 ° / 130 ° 
TFTLCD PANEL 
Recommend resolution  1440 x 900@60Hz 
Analog (75ohms, 0.7/1.0 Vp-p)  Yes Input Signal 
Digital No 
Separate Sync  Yes 
Composite Sync  No Sync Compatibility 
Sync on Green  No 
PC Yes 
Power Mac  Yes Compatibility TV...

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2.2 GENERAL SPECTION   
 
Test Resolution & Frequency 1440 x 900 @ 60Hz 
Test Image Size  Full Size 
Contrast and Brightness Controls  Factory Default:   
Contrast = 70%, Brightness = 100% 
 
2.3 VIDEO INTERFACE 
 
Analog Input Connector  DB-15 (Analog), refer the appendix A
 
Digital Input Connector  N/A 
Default Input Connector  Defaults to the first detected input 
Video Cable Strain Relief  Equal to twice the weight of the monitor for five minutes 
Video Cable Connector DB-15...

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2.4 POWER SUPPLY Power Supply (Adapter)  Part Number:  27-D003247 
Input Voltage Range  90 to 264 VAC 
Input Frequency Range 47 to 63 Hertz 
Short Circuit Protection OUTPUT CAN BE SHORTED WITHOUT DAMAGE 
Over Current Protection FUSE 3.15
A TY P I CA L AT  250 VA C  
Leakage Current  75 
MA (MAX) AT 240VAC / 50HZ 
Efficiency  80 % TYPICAL AT 100VAC @60HZ 
Fuse  INTERNAL AND NOT USER REPLACEABLE 
Power Dissipation 36 
WAT T S  
Max Input AC Current  1.6
 ARMS  @  nominal RANGE...

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2.5 ELECTRICAL REQUIREMENT 
Horizontal / Vertical Frequency Horizontal Frequency  30 – 82 kHz   
Vertical Refresh Rate 50 – 85* Hz. 
Maximum Pixel Clock  135 MHz 
(EDID file is 140MHz) 
Sync Polarity  Independent of sync polarity.  

Primary Presets 
1440 x 900 @ 60Hz 
 
User Presets 
Number of User Presets (recognized timings) Available: 10 presets total in FIFO configuration 
 
Changing Modes 
 
●  Maximum Mode Change Blank Time for image stability : 3 seconds (Max), excluding...

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2.6 FRONT PANEL CONTROLS AND INDICATORS 
Front Panel Hardware Controls 
 
Power Switch (Front Head)  Power Control, soft Power Switch. 
Power LED (Front Head)  Green – ON Orange – Active Off 
Dark = Soft Power Switch OFF 
Front Panel Controls (Head) 
[; X] [ 1 ] [ ▼] [▲ ] [ 2 ] [
] 
 
  [
] Power   
[ 1 ] BUTTON 1   
[ 2 ] Button 2 
[ ▲ ] UP ARROW BUTTON 
[ ▼ ] DOWN ARROW BUTTON 
[ ;  X] Audio Mute on/off 
 
Note: Power Button, Button 1 and Button 2 and Mute Button must be...