ViewSonic Q19wb-3 User manual

ViewSonic Q19wb-3
Model No. VS11578
19” Color TFT LCD Display
(Q19wb-3_SM Rev. 1a Oct. 2006)
ViewSonic 381 Brea Canyon Road, Walnut, California 91789 USA- [phone]
Service Manual

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Copyright
Copyright © 2006 by 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
Optiquest 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 10/31/2006 Initial Release Jamie Chang

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TABLE OF CONTENTS
1. Precautions and Safety Notices 1
2. Specification 4
3. Front Panel Function Control Description 10
4. Circuit Description 12
5. Adjustment Procedure 20
6. Troubleshooting Flow Chart 42
7. Recommended Spare Parts List 46
8. Exploded Diagram and Exploded Parts List 48
9. Block Diagram 52
10. Schematic Diagrams 53
11. PCB Layout Diagrams 61

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1. Precautions and Safety Notices
1. Precaution & Safety Notice
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. Aleakage 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

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Q19wb-3 series handling Notice
Correct Method Incorrect method
Correct Method Incorrect method
Correct Method Incorrect method

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Correct Method Incorrect method
Correct Method Incorrect method

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2. Specification
1. GENERAL REQUIREMENTS
General Specification
Test Resolution & Frequency 1440x900 @ 60Hz
Test Image Size Full Size
Contrast and Brightness Controls Factory Default:
Contrast = 80%, Brightness = 100%
2. SIGNAL INTERFACE
Video Interface
Input Connector (refer the appendix A) D-Sub = DB-15 (Analog)
Default Input Connector D-Sub
Video Cable Strain Relief Equal to twice the weight of the monitor for
five minutes
Video Cable Connector DB-15 Pin out Compliant DDC1/2B
Video RGB (Analog)
Video Signals Separate Sync / SOG / Composite
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/CI N/A
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 400, 640 x 480, 720 x 400,
800 x 600, 832 x 624, 1024 x 768,
1152 x 864, 1152 x 870,1280 x 1024,
1440 x 900,
Exclusions Not compatible with interlaced video

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3. Power
Internal Power Supply Delta EADP-45AF BF
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 5.0 A typical at 12.0 VDC
Leakage Current 0.75mA(Max) at 264VAC / 50Hz
Efficiency 75 % (min.)
Fuse Internal and not user replaceable
Power Dissipation 45 Watts (typ)
Max Input AC Current 1.2 Arms @ 90VAC, 0.7 Arms @264VAC
Inrush Current (Cold Start) 60 A (max) @ 115VAC
90A(Max)264VAC
Power Supply Cold Start Shall start and function properly when under full load, with all combinations of input voltage, input frequency, and operating
temperature.
Power Supply Transient Immunity Shall be able to withstand anANSI/IEEE C62.41-1980 6000V 200
ampere ring wave transient test with no damage.
Power Supply Line Surge Immunity Shall be able to withstand 1.5 times nominal
line voltage for one cycle with no damage.
Power Supply Missing Cycle Immunity
Shall be able to function properly,without
reset or visible screen artifacts, when ½
cycle of AC power is randomly missing at
nominal input.
Power SupplyAcoustics
The power supply shall not produce audible noise that would be
detectable by the user.
Audible shall defined to be in compliance with ISO 7779 (DIN
EN27779:1991) Noise
measurements of machines acoustics. Power
Switch noise shall not be considered.
Power Saving Operation(Method) VESA DPMS Signaling
On Mode < 40 W (Typ) / 36 W (max)
Power Consumption Active Off < 1 W
Recovery Time On Mode = N/A, Active Off < 5 sec
4. ELECTRICAL REQUIREMENTS
Horizontal /Vertical Frequency
Horizontal Frequency 31 – 81 kHz
Vertical Refresh Rate 50 – 75 Hz.
Maximum Pixel Clock 140 MHz
Sync Polarity Independent of sync polarity.
Timing Table AnalogItem Timing
Separated
Composite
SOG
Digital - TMDS
Remark
1 640 x 350 @ 70 Hz, 31.5 KHz
2 640 x 400 @ 70 Hz, 31.5 KHz
For Separated Sync, Switch
640x400@70Hz and 720x400@70Hz by
[AUTO]+[MENU]
short cut key (primary = 720x400@70Hz)

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3 640 x 480 @ 60 Hz, 31.5 KHz
4 640 x 480 @ 67 Hz, 35 KHz
5 640 x 480 @ 72 Hz, 37.9 KHz
6 640 x 480 @ 75 Hz, 37.5 KHz
7 720 x 400 @ 70 Hz, 31.5 KHz
8 800 x 600 @ 56 Hz, 35.1 KHz
9 800 x 600 @ 60 Hz, 37.9 KHz
10 800 x 600 @ 72 Hz, 48.1 KHz
11 800 x 600 @ 75 Hz, 49.6 KHz
12 832 x 624 @ 75 Hz, 49.7 KHz
13 1024 x 768 @ 60 Hz, 48.4 KHz
14 1024 x 768 @ 70 Hz, 56.5 KHz
15 1024 x 768 @ 72 Hz, 58.1 KHz
16 1024 x 768 @ 75 Hz, 60 KHz
17 1152 x 864 @ 75 Hz, 67.5 KHz
18 1152 x 870 @ 75 Hz, 68.7 KHz
19 1280 x 1024 @ 60 Hz, 64 KHz
20 1280 x 1024 @ 75 Hz, 80 KHz
21 1280 x 960 @ 60 Hz 59.7 KHz
22 1440 x 900 @ 60 Hz, 55.9 KHz
23 1440 x 900 @ 75 Hz, 70 KHz
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), it should recall factory setting when execute “Auto
Adjust”
● The monitor needs to do “Auto Adjust” the first time a new mode is detected
(see section “0-Touch™ FunctionActions”)
● While running Change Mode, Auto Adjust or Memory Recall, the image shall blank

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5. LCD Panel
1st Source Panel
Model number Hannstar HSD190MGW1-A00
Type Active Matrix TFT
Active Size 19.1"w
Pixel Arrangement RGB Vertical Stripe
Pixel Pitch 0.2835mm x 0.2835mm
Glass Treatment Anti-Glare
# of Backlights 4 CCFL
Backlight Life 50000 Hrs (Min)@6.5mA
300 cd/m2 (Typ after 30 minute warm up)Luminance (Center) –
CT = 6500K,
Contrast/ Brightness = Max 240 cd/m2 (Min after 30 minute warm up)
Brightness Uniformity 75% (min)
Contrast Ratio 700 :1 (Typ)
450 : 1 (Min)
Color Depth 16.2 million colors (6-bit+FRC panel)
Horizontal Viewing Angle 150 degrees (Typ) @ CR>10
130 degrees (Min) @ CR>10
Vertical Viewing Angle 140 degrees (Typ) @ CR>10
120 degrees (Min) @ CR>10
Response Time On/Off
10%-90% @ Ta=25°C Typical = 5 ms (Tr = 1.5 ms; Tf = 3.5 ms)
Maximun = 10 ms (Tr = 3ms; Tf = 7ms)
Mercury 3.5 mg per lamp
Panel Defects Please see Panel Quality Specifications.