ViewSonic VA702-3 User manual

ViewSonic VA702-3
VA702b-3
Model No. VLCDS27998-3W
VLCDS27998-4W
17” Color TFT LCD Display
(VA702-3_VA702b-3_SM Rev. 1aMay 2006)
ViewSonic 381 Brea Canyon Road, Walnut, California 91789 USA –[phone]
Service Manual

ViewSonic Corporation Confidential -Do Not Copy VA702-3_VA702b-3
i
Copyright
Copyright © 2006by ViewSonic Corporation. All rights reserved. No part of 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
Opt quest is a registered trademark of ViewSonic Corporation.
ViewSonic is a registered trademark of ViewSonic Corporation.
All other trademarks used within this document are the property of their respective owners.
Revision History
Revision
SM Editing Date ECR Number Description of Changes Editor
1a 05/02/2006 Initial Release J. Chang

ViewSonic Corporation Confidential -Do Not Copy VA702-3_VA702b-3
ii
TABLE OF CONTENTS
1. Precautions and Safety Notices 1
2. Specification 3
3. Front Panel Function Control Description 7
4. Circuit Description 9
5. Adjustment Procedure 17
6. Troubleshooting Flow Chart 40
7. Recommended Spare Parts List 42
8. Exploded Diagram and Exploded Parts List 45
9. Block Diagram 49
10. Schematic Diagrams 51
11. PCB Layout Diagrams 57

ViewSonic Corporation Confidential -Do Not Copy VA702-3_VA702b-3
1
1. Precautions and Safety Notices
1. 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 guide line
2. Safety Check :
Care should be taken while servicing this LCD display. Because of the high voltage used in the
inverter circuit. These voltage are exposed in such areas as the associated transformer circuits .
3. POWER SUPPLY REQUIREMENTS
The external power converter for this display utilizes AC and DC cords , AC cord is detachable , but
DC cord is permanently attached . Any attempt to replace another adapter could result in serious
problem on the display .
4. LEAKAGE CURRENT HOT CHECK
4-1 Plug the AC cord directly into the AC outlet. Do not use an isolation transformer during this
check.
4-2 Connect a 1500 ohm , 10 watt resistor , paralleled by a 0.15uF capacitor between each metallic
part and a good earth ground
4-3 Use an AC voltmeter with 1000 ohm / volt or more sensitivity and measure the AC voltage
across the combination 1500 ohm resistor and 0.15uF capacitor.
4-4 Move the resistor connection to each exposed metallic part and measure the voltage.
4-5 Reverse the polarity of the AC plug in the AC outlet and repeat the above measurement.
4-6 Voltage measured must not exceed 1.5 volt RMS, from any exposed metallic part to the ground.
A leakage current tester may be used in the above hot check, in which case any circuit measured
must not exceed 1.0 milliamp. In the case of a measurement exceeding the 1.0 milliamp value, a
rework is required to eliminate the chance of a shock hazard .
To Metal Parts
V
AC VOLTMETER
1500 10W
0.15u
.
Earth Ground

ViewSonic Corporation Confidential -Do Not Copy VA702-3_VA702b-3
2
Handling & Placing method
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

ViewSonic Corporation Confidential -Do Not Copy VA702-3_VA702b-3
3
2. Specification
GENERAL REQUIREMENTS
General Specifications
Test Resolution & Frequency 1280 x 1024 @ 60Hz
Test Image Size Full Size
Contrast and Brightness Controls Factory Default: Contrast = 70%, Brightness = 100%
SIGNAL INTERFACE
Video Interface
Analog Input Connector DB-15 (Analog)
Video Cable Strain Relief Equal to twice the weight of the monitor for five minutes.
Video Cable Connector DB-15 Pinout Compliant DDC 2B.
Video Signals Video RGB (Analog)
Video Impedance 75 Ohms (Analog)
Maximum PC Video Signal 950 mV with no damage to monitor
Maximum Mac Video Signal 1250 mV with no damage to monitor
Sync Signals TTL
DDC 1/2B Compliant with Revision 1.3
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, 1280 x 720, 1280 x 1024
Exclusions Not compatible with interlaced video.
Power
Power Supply
Internal Power Supply Part Number: ADP-40AFB
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 4.5 A TYPICAL AT 12 VDC
Leakage Current 3.5MA (MAX) AT 254VAC / 60HZ
Efficiency 70 % TYPICAL AT 115VAC FULL LOAD
Fuse INTERNAL AND NOT USER REPLACEABLE
Power Dissipation 36 WATTS (MAX)
Max Input AC Current 1.2 ARMS @ 90VAC, 0.8 ARMS @180VAC

ViewSonic Corporation Confidential -Do Not Copy VA702-3_VA702b-3
4
ELECTRICAL REQUIREMENTS
Horizontal / Vertical Frequency
Horizontal Frequency 30 –80 kHz
Vertical Refresh Rate 50 –85 Hz.
Maximum Pixel Clock 135 MHz
Sync Polarity Independent of sync polarity.
Primary Presets
Primary Preset 1280 x 1024 @ 60Hz
Look up table timing
<<Analog>>
640 x 350 @ 70Hz, 31.5kHz
640 x 480 @ 60Hz, 31.5kHz
640 x 480 @ 67Hz, 35.0kHz
640 x 480 @ 75Hz, 37.5kHz
640 x 480 @ 72Hz, 37.9kHz
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
1280 x 1024 @ 60Hz, 63.4kHz
1280 x 1024 @ 75Hz, 79.97kHz
21. 1280x720 @ 60Hz, 45kHz (HDTV)
Changing Modes
Maximum Mode Change Blank Time, for
image stability. Note:
1) Excluding “Auto Adjust” time
2) Under DOS mode (640 x 350, 720 x 400 & 640 x
400), there is no “Auto Adjust” feature.
3) The monitor needs to do “Auto Adjust” the first
time a new mode is detected.
3 seconds (Max)
1 seconds (Typ) for recognized timings
1-2 seconds (Typ) for unrecognized timing
.
Mode Change Image The image shall blank while the monitor changes modes.

ViewSonic Corporation Confidential -Do Not Copy VA702-3_VA702b-3
5
LCD Panel
1st Source Panel QD17EL0711
Type NORMALLY WHITE, TN, OPTICAL COMPENSATION FILM
Active Size 337.920 (H) x 270.336 (V)
Pixel Arrangement RGB Vertical Stripe
Pixel Pitch 0.264 mm
Glass Treatment ANTI GLARE
# of Backlights 4CCFL EDGE-LIGHT (2TOP / 2 BOTTOM)
Backlight Life 50,000 HOURS (TYP) / 40,000 HOURS (MIN)
Luminance –
Condition:
CT = 6500K, Contrast = Max, Brightness = Max
260 CD/M2 (TYP AFTER 30 MINUTE WARM UP)
220 CD/M2 (MIN AFTER 30 MINUTE WARM UP)
Brightness Uniformity 75 % Entire Area (minimum)
Contrast Ratio 500:1 (Typ), 300:1 (Min)
Color Depth 16 million colors (6 bit panel)
Viewing Angle (Horizontal) 140 deg @ CR>10, 160 deg @ CR>5
Viewing Angle (Vertical) 125 deg @ CR>10, 145 deg @ CR>5
Response Time
10%-90% @ Ta=25°C
8ms (Tr= 6 ms, Tf = 2 ms) (Typ)
TBD ms (Tr= TBD ms, Tf = TBD ms) (Max)
Panel Defects Please see Panel Quality Specifications.
MECHANICAL
Dimensions (Base attached unless otherwise specified)
Width 377.6 mm
Height 374.0 mm
Depth 195.6 mm
Depth (Head Only) 55.0 mm
Monitor Weight 4.1 kg / 9.0 lbs
Packaging Specification
Width 450 mm
Height 522 mm
Depth 135 mm
Gross Weight 5.2 kg (11.45lb)
# units per Pallet 36/72 (air/sea)
20’/40’ Container Loading, Palletized 720/1728 pieces
Ergonomics
Tilt Up 20 DEGREES MINIMUM
Tilt Down -5degrees
Swivel Right 0degrees
Swivel Left 0degrees
Height Adjust 0mm
Pivot 0DEGREES (CLOCKWISE)

ViewSonic Corporation Confidential -Do Not Copy VA702-3_VA702b-3
6
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

ViewSonic Corporation Confidential -Do Not Copy VA702-3_VA702b-3
7
3. Front Panel Function Control Description
Main Menu
With On View controls
Front Control Panel
shown below in detail
Power On / OffDisplays the Main Menu or
exits the controlscreen
and saves adjustments.
Displays the control screen for the
highlighted control.Also toggles
between two controls on some screens.
Also a shortcut to auto image adjust
Power light
Green = ON
Orange=power
saving
Scrolls through menu options and
adjusts the displayed control.
Also a shortcut to display the
Contrast adjustment control screen.