ViewSonic VX2255wmb-4 User manual

ViewSonic VX2255wmb-4
VX2255wmh-4
Model No. VS11661
22” wide Color TFT LCD Display
(VX2255wmb-4_VX2255wmh-4_SM Rev. 1a Sep. 2007)
ViewSonic 381 Brea Canyon Road, Walnut, California 91789 USA- [phone]
Service Manual

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Copyright
Copyright © 2007 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.
Product disposal at end of product life
The lamp in this product contains mercury. Please dispose of in accordance with local, state or
federal laws.
Revision History
Revision SM Editing Date ECR Number Description of Changes Editor
1a 9/14/2007 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 ..................................................................... 23
4. Circuit Description ............................................................................................................. 29
5. Adjusting Procedure..........................................................................................................31
6. Trouble Shooting Flow Chart ............................................................................................ 44
7. Block Diagrams ................................................................................................................ 53
8. Schematic Diagrams ........................................................................................................ 54
9. PCB Layout Diagrams ...................................................................................................... 61
10. Exploded Diagram And Spare Parts List........................................................................ 65
11. Recommended Spare Parts List .................................................................................... 70

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1. Precautions and Safety Notices
1. SAFETY PRECAUTIONS
This monitor is manufactured and tested on a ground principle that a user’s safety comes first. However,
improper used or installation may cause damage to the monitor as well as to the user.
WARNINGS:
zThis monitor should be operated only at the correct power sources indicated on the label on the rear
of the monitor. If you’re unsure of the power supply in you residence, consult your local dealer or
Power Company.
zUse only the special power adapter that comes with this monitor for power input.
zDo not try to repair the monitor by yourself, as it contains no user-serviceable parts. Only the
qualified technician can repair it.
zDo not remove the monitor cabinet. There are high-voltage parts inside that may cause electric shock
to human bodies.
zStop using the monitor if the cabinet is damaged. Have it checked by a service technician.
zPut your monitor only in a lean, cool, dry environment. If it gets wet, unplug the power cable
immediately and consult your closed dealer.
zAlways unplug the monitor before cleaning it. Clean the cabinet with a clean, dry cloth. Apply
non-ammonia based cleaner onto the cloth, not directly onto the glass screen.
zDo not place heavy objects on the monitor or power cord.
2. PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special safety visual inspections and the
protection afforded by them cannot necessarily be obtained by using replacement components rated for
higher voltage, wattage, etc. Before replacing any of these components read the parts list in this manual
carefully. The use of substitute replacement parts, which do not have the same safety characteristics as
specified in the parts list, may create shock, fire, or other hazards.
3. SERVICE NOTES
zWhen replacing parts or circuit boards, clamp the lead wires around terminals before soldering.
zKeep wires away from high voltage, high temperature components and sharp edges.
zKeep wires in their original position so as to reduce interference.
zAdjustment of this product please refers to the user’ manual.

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4. Handing and Placing Methods
Correct Methods: Incorrect Methods:
Only touch the metal frame of the LCD panel or the front
cover of the monitor, Do not touch the surface of the panel.
Surface of the panel is pressed by fingers and that may
cause “Mura”
Take out the monitor with cushions Take out the monitor by grasping the LCD panel, and that
may cause “Mura”.

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Correct Methods: Incorrect Methods:
Place the monitor on a clean and soft foam pad. Place the monitor on foreign objects. That could Scratch the
surface of the panel or cause “Mura”.
The panel is placed facedown on the lap. That may cause
“Mura”

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2. Specification
FEATURES VX2255wmb/wmh-4
Size 22" wide
Luminance (Typ) 300 cd/㎡
Contrast Ratio (Typ) 1000:1
Colors 16.7 M (6 bits + 2 bits FRC)
Response Time 5 ms(on/off) / 3ms(G to G / avg)
Viewing Angle (H/V) 170° / 160 °
TFTLCD PANEL
Recommend resolution 1680x1050@60Hz
Analog Yes (75ohms, 0.7/1.0 Vp-p)
Input Signal Digital Yes
Separate Sync Yes
Composite Sync Yes
Sync Compatibility
Sync on Green Yes
PC Yes
Power Mac Yes
Compatibility
TV Box Yes
Power Voltage AC 100-240V, 50/60Hz Yes
On Mode(Typ) < 45 W (without audio)
Power Consumption Off Mode (Max) ≦1 W
Audio 2W / THD 10% (Max) Yes
WebCam 1.3M / USB2.0 / Windows XP
Cable (type A to type B) Yes
Tilt Yes ( 20 ° and -5 °)
Swivel 360°
Pivot No
Ergonomics
Height Adjust 80mm
OSD Control [ 1 ] [▲] [▼] [ 2 ] // [ ] Yes
Physical (W x H x D) 528(W) x 450(H) x 225(D) mm
Dimension Package (W x H x D) 572(W) x 525(H) x 267(D) mm
Physical (Net Weight) 6.0 Kg / 13.3 lbs
Weight Package (Gross Weight) 8.4 Kg / 18.6 lbs
Temperature (℉/℃) 32℉-104℉/+0℃-+40℃
Operating Condition Humidity (%) 10 % - 90 %
Temperature (℉/℃) -4℉-140℉/-20℃-60℃
Storage Condition Humidity (%) 10 % - 90 %
Regulation
Global: CB, MPR II,WEEE,ROHS
VSA:UL, cUL, FCC-B, TUV-S, NOM, Energy Star
VSE:TUV/ERGO(covers ISO13406-2&MPR II),CE
GOST-R+Hygienic ,SASO , ENERGY, Ukraine
VSI: BSMI, PSB, C-TICK, MIC, VCCI, Green Mark
VSCN:CCC

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Product definition and specification
VSA VSAP VSE VSCN
Region
(M) (A)/(P)/(J)/(U)/(N) (E)/(U)/(EU) (G)
Product Name VX2255wmb/wmh-4
Model Number VS11661
OSD Languages English, French, German, Italian, Spanish, Finnish, Russian,
Korean, Japanese, Traditional Chinese, Simplified Chinese
TFT LCD Panel and Model #
1st INN MT220W W01 V.0
2nd CMO M220Z1-L03
3rd INN MT220W W01 V2
Scalar Mstar, Model # : TSUMO58CWHJ-LF
Input Signal D-Sub / DVI-D
Sync Compatibility Separate / Composite / SOG
Audio 2W
Power Consumption Built-in/ under 50 W (max) / 45 W(typ)
(without audio)
Power Cable Refer to Appendix G
Analog Cable (1.8 m, color : black), with PC
2001 and Hot Plug Detect &DDC YES
DVI-D Cable YES
WebCam
Hardware spec --- 1.3M pixel
OS support --- Windows XP/ Vista
Interface support --- USB 2.0 (type A to type B)
Program support --- Skype / Windows Live Messenger
ViewSonic CD Wizard
ViewSonic Quick Start Guide
WebCam AP Wizard
Arabic, English, Finnish, Spanish, German,
Italian, Japanese, Swedish, Polish, Korean
Portuguese, Russian, French, Greek, Dutch, Turkish,
Simplified Chinese, Traditional Chinese, Czech, Hungarian
Screen Protector Mylar YES
Extrme Label (?ms) NO
DCR sticker (4000:1) / 2pcs YES
Service Insert (new version) YES NO NO NO
Warranty Sticker NO NO NO No
Warranty Card
(China only / new version) NO NO NO YES
Carton Sticker
(China only / new version) NO NO NO YES
PE bag of Carton NO NO NO YES

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2-1 GENERAL specification
Test Resolution & Frequency 1680x1050@ 60Hz
Test Image Size Full Size
Contrast and Brightness Controls Factory Default:
Contrast = 70%, Brightness = 100%
2-2 VIDEO INTERFACE
Analog Input Connector DB-15 (Analog), refer the appendix A
Digital Input Connector DVI-D
Audio input 1 3.5Mini Jack
Headphone output 3.5Mini Jack
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
Pin out Compliant DDC/CI / 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)
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/2B Compliant with Revision 1.3
DDC/CI Compliant with Revision 1.1
HDCP HDCP code inside and compatible
Sync Compatibility Separate Sync, Composite Sync, SOG
Video Compatibility Shall be compatible with all PC type computers,
Macintosh computers, and after market video cards
640x350 640x400 640x480 720x400
720x480 800x600 832x624 1024x768
1152x864 1152x870 1280x720 1280x768
1280x960 1280x1024 1360x768 1400x1050
1440x900 1600x1200 1680x1050
Resolution Compatibility
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

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2-3 POWER SUPPLY
Internal Power Supply Part Number: 790961400600R
Input Voltage Range AC90~264 (WORLDWIDE)
Input Frequency Range 47 TO 64 HERTZ
Short Circuit Protection OUTPUT CAN BE SHORTED WITHOUT DAMAGE
Over Current Protection 3.3~4.5A TYP. AT 5 VDC
( PROTECT WHEN SHORT CIRCUIT )
Leakage Current 3.5MA (MAX) AT 264VAC / 50HZ
Efficiency 80 % TYPICAL AT 115VAC FULL LOAD
Fuse INTERNAL AND NOT USER REPLACEABLE
Power Dissipation < 45 WAT T S ( T Y P ) (without audio)
Max Input AC Current 1.6A (MAX)
Inrush Current
(Cold Start)
80 A MAX./ 240VAC / 50HZ
(COLD START AT 25℃,FULL LOAD)
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 AN ANSI/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 Supply Acoustics
The power supply shall not produce audible noise that would be
detectable by the user. Audible shall define to be in compliance
with ISO 7779 (DIN EN27779:1991) Noise measurements of
machines acoustics. Power Switch noise shall not be considered
US Type Power Cable
Color = Black
Separate 3-prong NEMA 5-15P type plug. Length = 1.8m.
Connects to display.
European Type Power Cable
Color = Black
Schuko CEE7-7 type plug.
Length = 1.8m, Connects to display.
CCC Type Power Cable
Color = Black
Separate 3-prong type plug.
Length = 1.8m. Connects to display.
PSE Type Power Cable
Color = Black
Separate 2-prong NEMA 1-15P type plug.
Length = 1.8m. Connects to display.
Power Saving Operation(Method) VESA DPMS Signaling
Power Consumption
On Mode <45W (Typ) / under 50W (Max) (without audio)
Saving Mode < 2 W@230VAC 50Hz
Off Mode < 1 W @230VAC 50Hz
(DC Power Off; Meet to Energy Star Ver4.0 Tier2)
Recovery Time On Mode = N/A, Active Off < 3 sec