ViewSonic VLCDS25973-4W User manual

Model No. VLCDS25973-4W/5W
19” Color TFT LCD Display
Service Manual
ViewSonic VP912s/b1
ViewSonic
381 Brea Canyon Road, Walnut, California 91789 USA - [phone]
(VP912s/b_SM_902 Rev. 1bMar. 2005)

Copyright
Copyright
¤
2005by ViewSonic Corporation. All rights reserved. No partof this publication may be
reproduced, transmitted, transcribed, 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 otherwise, without the prior written permission of ViewSonic Corporation.
Disclaimer
ViewSonic makes no representations or warranties, either expressed or implied, with respect to the
contents hereof and specifically disclaims any warranty of merchantability or fitness for any particular
purpose. Further, ViewSonic reserves the right to revise this publication and to make changes from time
to time in the contents hereof without obligation of ViewSonic to notify any person of such revision or
changes.
Trademarks
ViewSonic is a registered trademark of ViewSonic Corporation.
All other trademarks used within this document are the property of their respective owners.
Optiquest is a registered trademark of ViewSonic Corporation.
Revision History
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DCN Number ECR Number
Documents Number Description of Changes EditorRevision SM Editing Date
1a 08/26/04 4644 Initial Release A. Lu
1b 03/04/05
5005 Panel Change from AUO M190EN04 V1(12ms) A. Lu
4819 Scaler GM5120
to AUO M190EN04 V4 (12ms),

TABLE OF CONTENTS
2. Specification
3. Front Panel Function Control Description
4. Circuit Description
6. Troubleshooting Flow Chart
9. Block Diagram
10. Schematic Diagrams
7. Recommended Spare Parts List
1. Precautions and Safety Notices
5. Adjustment Procedure
8. Exploded Diagram and Spare Parts List
11. PCB Layout Diagrams
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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) If smoke, abnormal noise, or strange odor is present, immediately switch the LCD display off.
(7) Do not touch the LCD panel surface with sharp or hard objects.
(8) Do not place heavy objects on the LCD display, video cable, or power cord.
(9) Do not use abrasive cleaners, waxes or solvents for your cleaning.
(10) Do not operate the product under the following conditions:
- Extremely hot, cold or humid environment.
-Areas containing excessive dust and dirt.
- Near any appliance generating a strong magnetic field.
- In direct sunlight.
2. Caution
No modification of any circuit should be attempted. Service work should only be performed after you are thoroughly familiar
with all of the following safety checks and servicing guidelines.
3. Safety Check
Care should be taken while servicing this LCD display. Because of the high voltage used in the inverter circuit, the voltage is
exposed in such areas as the associated transformer circuits.
4. LCDModule Handling Precautions
4.1 Handling Precautions
(1) Since front polarizer is easily damaged, pay attention not to scratch it.
(2)Be sure to turn off power supply when connecting or disconnecting input connector.
(3)Wipe off water drops immediately. Long contact with water may cause discoloration or spots.
(4) When the panel surface is soiled, wipe it with absorbent cotton or other soft cloth.
(5) Since the panel is made of glass, it may break or crack if dropped or bumped on hard surface.
(6)Since CMOSLSI isusedinthis module, take care of static electricity and ensure human earth when handling.
(7)Do not open or modify the Module Assembly.
(8)Do not press the reflector sheet at the back of the module in any direction.
(9)In the event that a Module must be put back into the packing container slot after it was taken out of the
container, do not press the center of the CCFL Reflector edge. Instead, press at the far ends of the
CFL Reflector edge softly. Otherwise the TFT Module may be damaged.
(10) At the insertion or removal of the Signal Interface Connector, be sure not to rotate or tilt the Interface
Connector of the TFT Module.
1. Precautions and Safety Notices
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(11) After installation of theTFT Module intoan enclosure(LCDmonitor housing, for example), do not twist or
bend the TFT Module even momentarily. When designing the enclosure, it should be taken into consideration
that no bending/twisting forces may be applied to the TFT Module from outside. Otherwise theTFT Module
may be damaged.
(12) The cold cathode fluorescent lamp in the LCD contains a small amount of mercury. Please follow local
ordinances or regulations fordisposal.
(13) The LCD module contains a small amount of materials having no flammability grade. The LCD module
should be supplied with power that complies with the requirements of Limited Power Source
(IEC60950 or UL1950), or an exemption should be applied for.
(14) The LCD module is designed so that the CCFL in it is supplied by a Limited Current Circuit (IEC60950
or UL1950). Do not connect theCCFL to a HazardousVoltage Circuit.
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5. Handling Methods
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Only touch the metal frame of the LCD
panel or the front cover of the monitor. Do
not touch the surface of the polarizer.
If the surface of the LCD panel is pressed
by fingers, that may cause "MURA."
Take out the monitor by grasping the cushions.
If the monitor is removed by grasping the
LCD panel, that may cause "MURA."
Correct Methods: Incorrect Methods:

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Place the monitor on a clean and soft
foam pad.
If the monitor is placed on foreign objects,
that could scratch the surface of the panel
or cause "MURA."
If the panel is placed facedown on the
lap, that may cause "MURA."

1. General Requirements
General Specifications
Test Resolution & Frequency 1280x1024 @ 60Hz
Test Image Size Full Size
Contrast and Brightness Controls Factory Default:
Contrast = 50%, Brightness = 100%
2. Signal Interface
Video Interface
Input Connector 1 (Analog 1) DB-15 (Analog)
Input Connector 2 (Analog 2) DB-15 (Analog)
Digital Input Connector DVI-I (Digital)
Default Input Connector Defaults to the first detected input
Video Cable Connector DB-15 Pin out Compliant DDC 2B
Video Signals 1. Video RGB (Analog)
Separate, Composite, and Sync on Green
2. TMDS (Digital)
Video Impedance 75 Ohms (Analog), 100 Ohms (Digital)
Exclusions Not compatible with interlaced video
3. Power
Power Supply
Internal Power Supply Primary : LSE0204A1250
2nd source: Tiger power TOF 5001
Input Voltage Range 90 to 264 VAC
Over Current Protection 7.0 A typical at 12.0 VDC
Power Dissipation 50 Watts (typ.)
2. Specification
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4. Electrical Requirements
Horizontal / Vertical Frequency
Horizontal Frequency 24 – 82 KHz
Vertical Refresh Rate 50 – 85* HZ.
FOR RESOLUTION 1280 X 1024, THE
VERTICAL RFRESH RATE UP TO 75 HZ; FOR
THE REST RESOLUTIONS, THE VERTICAL
REFRESH RATE UP TO 85HZ
Maximum Pixel Clock 135 MHz
Primary Presets 1280x1024 @ 60Hz
Look up table timing
<<Analog>>
640 x 350 @ 70Hz, 31.5kHz
640 x 400 @ 60Hz, 31.5kHz
640 x 400 @ 70Hz, 31.5kHz
640 x 480 @ 50Hz, 24.7kHz
640 x 480 @ 60Hz, 31.5kHz
640 x 480 @ 67Hz, 35.0kHz
640 x 480 @ 72Hz, 37.9kHz
640 x 480 @ 75Hz, 37.5kHz
640 x 480 @ 85Hz, 43.27kHz
720 x 400 @ 70Hz, 31.5kHz
800 x 600 @ 56Hz, 35.1kHz
800 x 600 @ 60Hz, 37.9kHz
800 x 600 @ 75Hz, 46.9kHz
800 x 600 @ 72Hz, 48.1kHz
800 x 600 @ 85Hz, 53.7kHz
832 x 624 @ 75Hz, 49.7kHz
1024 x 768 @ 60Hz, 48.4kHz
1024 x 768 @ 70Hz, 56.5kHz
1024 x 768 @ 72Hz, 58.1kHz
1024 x 768 @ 75Hz, 60.0kHz
1024 x 768 @ 85Hz, 68.67kHz
1152 x 864 @ 75Hz, 67.5kHz
1152 x 870 @ 75Hz, 68.7kHz
1280 x 1024 @ 60Hz, 63.4kHz
1280 x 1024 @ 75Hz, 79.97kHz
1280x 720 @ 60Hz, 45kHz (HDTV)
<<Digital>>
640 x 350 @ 70Hz, 31.5kHz
640 x 400 @ 60Hz, 31.5kHz
640 x 400 @ 70Hz, 31.5kHz
640 x 480 @ 50Hz, 24.7kHz
640 x 480 @ 60Hz, 31.5kHz
640 x 480 @ 67Hz, 35.0kHz
640 x 480 @ 72Hz, 37.9kHz
640 x 480 @ 75Hz, 37.5kHz
640 x 480 @ 85Hz, 43.27kHz
720 x 400 @ 70Hz, 31.5kHz
800 x 600 @ 56Hz, 35.1kHz
800 x 600 @ 60Hz, 37.9kHz
800 x 600 @ 75Hz, 46.9kHz
800 x 600 @ 72Hz, 48.1kHz
800 x 600 @ 85Hz, 53.7kHz
832 x 624 @ 75Hz, 49.7kHz
1024 x 768 @ 60Hz, 48.4kHz
1024 x 768 @ 70Hz, 56.5kHz
1024 x 768 @ 72Hz, 58.1kHz
1024 x 768 @ 75Hz, 60.0kHz
1024 x 768 @ 85Hz, 68.67kHz
1152 x 864 @ 75Hz, 67.5kHz
1152 x 870 @ 75Hz, 68.7kHz
1280 x 1024 @ 60Hz, 63.4kHz
1280 x 1024 @ 75Hz, 79.97kHz
1280x 720 @ 60Hz, 45kHz (HDTV)
Changing Modes
zMaximum Mode Change Blank Time for
image stability : 3 seconds (Max), excluding
“Auto Adjust” time
zUnder DOS mode (640 x 350, 720 x 400 &
640 x 400), it should recall factory setting
when execute “Auto Adjust” by “0-Touch™”
zThe monitor needs to do “Auto Adjust” the
first time a new mode is detected (see section
“0-Touch™ Function Actions”)
zWhile running Change Mode, Auto Adjust or
Memory Recall, the image shall blank
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5. LCD Panel
Panel Characteristics
Model number AUO M190EN04
Type TN type with LVDS interface
Active Size 376.32 (H) x 301.06 (V)
Pixel Arrangement RGB Vertical Stripe
Pixel Pitch 0.294 mm
GLASS TREATMENT Anti Glare (Hard coating 2H)
# OF BACKLIGHTS 4 CCFL edge-light (2 top / 2 bottom)
BACKLIGHT LIFE 50,000 (Typ) / 40,000 Hours (Min)
Luminance (Center) – CT = 6500K
Contrast/ Brightness = Max
400 cd/m2 (Typ after 30 minute warm up)
350 cd/m2 (Min after 30 minute warm up)
Brightness Uniformity 75% (Typ) / 70% (Min) Entire Area
Contrast Ratio 450:1 (typ), 250:1 (min)
Color Depth 16 million colors (6+2 bit)
Viewing Angle (Horizontal, CR>10) Minimum: 130º (±65º)
Typical: 135º (+70º/-65º)
Viewing Angle (Vertical, @ CR>10) Minimum: 125º (+65º/-60º)
Response Time
10%-90% @ Ta=25°C
12 ms (Tr= 3.6 ms, Tf = 8.4 ms) (typ)
21 ms (Tr= 6.3 ms, Tf = 14.7 ms) (max)
6. Mechanical
Dimensions
Width 416 mm (16.4 inch)
Height 460 mm (18.1 inch)
Depth 238 mm (9.4 inch)
Monitor Weight 7.5 kg / 16.5 lbs
Ergonomics
Tilt Up From 0º up to ≧20º+/-2º
Tilt Down From 0º down to -3º ~ -5 º
7. Environmental
Environmental Conditions
Operating Temperature 0°C to +40°C
Storage Temperature -20°C to +60°C
Operating Relative Humidity 20% to 90% RH Non-Condensing
Storage Relative Humidity 5% to 90% RH Non-Condensing
Operating Altitude 0 to +3,000 meters
Storage Altitude 0 to +12,000 meters
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