ViewSonic vx912-1 User manual

Model No. VS10162
19” Color TFT LCD Display
Service Manual
ViewSonic VX912-1
ViewSonic
381 Brea Canyon Road, Walnut, California 91789 USA - [phone]
(VX912_SM_836 Rev. 1aOct. 2004)

Copyright
Copyright
¤
2004by 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 10/15/044460 Initial Release A. Lu

TABLE OF CONTENTS
2. Specification
3. Front Panel Function Control Description
4. Circuit Description
6. Trouble Shooting Flow Chart
9. Block Diagram
10. Schematic Diagrams
7. Recommended Spare Parts List
1. Precautions and Safety Notices
5. Adjusting 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 high quality andsafety approved AC/DCpower cord.
(5) Disconnect the power plug from AC outlet if the product is not 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 susceptible to excessive dustand dirt.
- Near any appliance generating a strong magnetic field.
- Place 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 inserting or disconnecting from input connector.
(3) Wipe off water drop 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 CMOS LSI is used in this module, take care of static electricity and insure human earth when handling.
(7) Do not open nor modify the Module Assembly.
(8) Do not press the reflector sheet at the back of the module to any directions.
(9) In case if a Module has to be put back into the packing container slot after once it was taken out from 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 nor tilt the Interface
Connector of the TFT Module.
1. Precautions and Safety Notices
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(11) After installation of the TFT Module into an enclosure (LCD monitor housing, for example), do not twist nor
bend the TFT Module even momentary. At designing the enclosure, it should be taken into consideration that
no bending/twisting forces are applied to the TFT Module from outside. Otherwise the TFT Module may be
damaged.
(12) Cold cathode fluorescent lamp in LCD contains a small amount of mercury. Please follow local ordinances or
regulations for disposal.
(13) Small amount of materials having no flammability grade is used in the LCD module. The LCD module should
be supplied by power complied with requirements of Limited Power Source (IEC60950 or UL1950), or be
applied exemption.
(14) The LCD module is designed so that the CFL in it is supplied by Limited Current Circuit (IEC60950 or
UL1950). Do not connect the CFL in Hazardous Voltage Circuit.
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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“.
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Correct Methods : Incorrect Methods :
Place the monitor on a clean & soft foam pad . Place the monitor on foreign objects .
That could scratch the surfaceof panel
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lGENERAL specification
Test Resolution & Frequency 1280x1024 @ 60Hz
Test Image Size Full Size
Contrast and Brightness Controls Factory Default:
Contrast = 70%, Brightness = 100%
lVIDEO INTERFACE
Analog Input Connector DB-15 (Analog), refer the appendix A
Digital Input Connector DVI-I(Digital), refer the appendix B
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 Pinout Compliant DDC 1/2B
Video Signals 1. Video RGB (Analog) Separate, Composite, and Sync on Green
2. TMDS (Digital)
Video Impedance 75 Ohms (Analog), 100 Ohms (Digital)
Maximum PC Video Signal 950 mV with no damage to monitor
Maximum Mac Video Signal 1250 mV with no damage to monitor
Sync Signals LVDS
DDC 1/2B Compliant with Revision 1.3
Sync Compatibility Separate Sync, Composite Sync, SOG
Video Compatibility Shall be compatible with all PC type computers,
Macintosh computers, and after market video cards
Resolution Compatibility
640 x 350*, 640 x 480, 720 x 400*(640 x 400*), 800 x
600, 832 x 624, 1024 x 768, 1152 x 864, 1152 x 870,
1280 x 720, 1280 x 960, 1280 x 1024
* The image vertical size might not be full screen.
But the image vertical position should be at the center.
Exclusions Not compatible with interlaced video
lPOWER SUPPLY
Internal Power Supply Part Number: FSP035-1PI01
Input Voltage Range 90 TO 264 VAC
Input Frequency Range 47.5 TO 63 HERTZ
Short Circuit Protection Output can be shorted without damage
Over Current Protection 3.5 A typical at 12.0 VDC ( Protect when short circuit )
Leakage Current 0.75mA (Max) at 264VAC / 50Hz
EFFICIENCY 77 % typical at 115VAC Full Load
Fuse Internal and not user replaceable
Power Dissipation 35 Watts(typ)
Max Input AC Current 1.2 Arms @ 90VAC, 0.7 Arms @265VAC
2. Specification
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lELECTRICAL REQUIREMENT
Horizontal / Vertical Frequency
Horizontal Frequency 24–82 KHZ
Vertical Refresh Rate 50–85* HZ.
* FOR RESOLUTION 1280 X 1024, THE VERTICAL
REFRESH RATE UP TO 75 HZ; FOR THE REST OF
RESOLUTIONS, THE VERTICAL REFRESH RATE
UP TO 85HZ
Maximum Pixel Clock 135 MHz
Sync Polarity Independent of sync polarity.
lTiming Table
Item Timing Analog Digital
1640 x 350 @ 70Hz, 31.5kHz Yes Yes
2640 x 400 @ 60Hz, 31.5kHz Yes Yes
3640 x 400 @ 70Hz, 31.5kHz Yes Yes
4640 x 480 @ 50Hz, 24.7kHz Yes Yes
5640 x 480 @ 60Hz, 31.5kHz Yes Yes
6640 x 480 @ 67Hz, 35.0kHz Yes Yes
7640 x 480 @ 72Hz, 37.9kHz Yes Yes
8640 x 480 @ 75Hz, 37.5kHz Yes Yes
9640 x 480 @ 85Hz, 43.27kHz Yes Yes
10 720 x 400 @ 70Hz, 31.5kHz Yes Yes
11 800 x 600 @ 56Hz, 35.1kHz Yes Yes
12 800 x 600 @ 60Hz, 37.9kHz Yes Yes
13 800 x 600 @ 75Hz, 46.9kHz Yes Yes
14 800 x 600 @ 72Hz, 48.1kHz Yes Yes
15 800 x 600 @ 85Hz, 53.7kHz Yes Yes
16 832 x 624 @ 75Hz, 49.7kHz Yes Yes
17 1024 x 768 @ 60Hz, 48.4kHz Yes Yes
18 1024 x 768 @ 70Hz, 56.5kHz Yes Yes
19 1024 x 768 @ 72Hz, 58.1kHz Yes Yes
20 1024 x 768 @ 75Hz, 60.0kHz Yes Yes
21 1024 x 768 @ 85Hz, 68.67kHz Yes Yes
22 1152 x 864 @ 75Hz, 67.5kHz Yes Yes
23 1152 x 870 @ 75Hz, 68.7kHz Yes Yes
24 1280 x 1024 @ 60Hz, 63.4kHz Yes Yes
25 1280 x 1024 @ 75Hz, 79.97kHz Yes Yes
26 1280x720 @ 60Hz, 45kHz (HDTV) Yes Yes
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lTFT LCD PANEL
1st Source Panel
Model number LPL LM190E03 B4N2/B4N4
Type TN type with LVDSinterface
Active Size 376.3 (H) x 301.1 (V)
Pixel Arrangement RGB Vertical Stripe
Pixel Pitch 0.294 mm
GLASS TREATMENT Anti Glare (Hard coating 3H)
# OF BACKLIGHTS 4CCFL edge-light (2top / 2bottom)
BACKLIGHT LIFE 50,000 Hours (Min)
Luminance (5-point) –
Condition:
CT = 6500K, Contrast = Max, Brightness = Max
250 cd/m2 (Typ after 30 minute warm up)
200 cd/m2 (Min after 30 minute warm up)
Brightness Uniformity ≧77%% Entire Area
Contrast Ratio 500:1 (typ), 300:1 (min)
Color Depth 16.2 million colors (6bits + 2 bits FRC)
Viewing Angle (Horizontal) @ CR>10
Typical: 140º(±70º)
Minimum: 120º(±60º)
@ CR>5
Typical: 160º(±80º)
Minimum: 140º(±70º)
VIEWING ANGLE (VERTICAL) @ CR>10
Typical: 140º(±70º)
Minimum: 120º(±60º)
@ CR>5
Typical: 160º(±80º)
MINIMUN: 140º(±70º)
Response Time
10%-90% @ Ta=25°C 12 ms (Tr= 2ms, Tf = 10 ms) (typ) 25 ms (Tr= 5ms, Tf = 20 ms) (max)
Panel Defects Please see Panel Quality Specifications.
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