ViewSonic Va1912wb 3 Service Manual

 
 
ViewSonic VA1912w-3  VA1912wb-3 
Model No. VS10866 
19” Color TFT LCD  Display 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
(VA1912w-3_VA1912wb-3_SM Rev. 1a Aug. 2006) 
ViewSonic 381 Brea Canyon Road, Walnut, California 91789 USA - (800) 888-8583 
Service Manual  

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ViewSonic Corporation 
    Confidential - Do Not Copy     VA1912w-3_VA1912wb-3 
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....

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ViewSonic Corporation 
    Confidential - Do Not Copy     VA1912w-3_VA1912wb-3 
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 Exploded Parts List  49
9. Block Diagram  51
10. Schematic Diagrams 52
11.  PCB Layout Diagrams  59
 
  

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ViewSonic Corporation 
    Confidential - Do Not Copy     VA1912w-3_VA1912wb-3 
1. Precautions and Safety Notices 
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...

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ViewSonic Corporation 
    Confidential - Do Not Copy     VA1912w-3_VA1912wb-3 
 
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...

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ViewSonic Corporation 
    Confidential - Do Not Copy     VA1912w-3_VA1912wb-3 
2. Specification 
2.1 INSTRUCTION   
FEATURES  VA1912w-3 / VA1912wb-3 
Size  19” wide 
Luminance (Typ, cd/㎡)  300 cd/㎡ 
Contrast Ratio (Typ)  700:1 
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 Yes 
Separate Sync  Yes 
Composite Sync  No Sync...

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ViewSonic Corporation 
    Confidential - Do Not Copy     VA1912w-3_VA1912wb-3 
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                                         DVI-D
Default Input Connector  Defaults to the first detected input 
Video Cable...

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ViewSonic Corporation 
    Confidential - Do Not Copy     VA1912w-3_VA1912wb-3 
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...

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ViewSonic Corporation 
    Confidential - Do Not Copy     VA1912w-3_VA1912wb-3 
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.  
 
Timing Table
  
Item Timing  Analog Digital 
1  640 x 350 @ 70Hz, 31.5kHz  Yes  Ye s 
2  640 x 400 @ 60Hz, 31.5kHz  Yes*  Ye s 
3  640 x 400 @ 70Hz, 31.5kHz  Yes  Ye s 
4  640 x 480 @...

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ViewSonic Corporation 
    Confidential - Do Not Copy     VA1912w-3_VA1912wb-3 
Primary Presets 
1440 x 900 @ 60Hz 
 
User Presets 
Number of User Presets (recognized timings) Ava ilable: 10 presets total in FIFO configuration 
 
Changing Modes 
 
●  Maximum Mode Change Blank Time for image stability : 3 seconds (Max), excluding “Auto Adjust” time       
●  Under DOS mode (640 x 350, 720 x 400 & 640 x 400), there is no “Auto Adjust” feature.  
●  The monitor needs to do “Auto Adjust” the first time...