ViewSonic Vx2235wm 5 Service Manual

							
 
 
ViewSonic VX2235wm-1 
Model No. VS11349 
22” Color TFT LCD  Display 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
(VX2235wm-1_SM Rev. 1a Aug. 2006) 
ViewSonic 381 Brea Canyon Road, Walnut, California 91789 USA - (800) 888-8583 
Service Manual  
						

							
ViewSonic Corporation Confidential - Do Not Copy    VX2235wm-1 
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Copyright 
Copyright © 2006 by ViewSonic Corporation.    All  rights reserved.    No part of this publication 
may be reproduced, transmitted, tran scribed, 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 ot herwise, 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 trademar k of ViewSonic Corporation. 
ViewSonic is a registered trademar k of ViewSonic Corporation. 
All other trademarks used within this document ar e the property of their respective owners. 
 
 
 
Revision History 
Revision  SM Editing Date  ECR Number  Description of Changes  Editor 
1a  8/14/2006      Initial Release  J. Chang 
       
       
       
       
       
       
  
						

							
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TABLE OF CONTENTS 
 
 
1.  Precautions and Safety Notices    1
2. Specification   3
3.  Front Panel Function Control Description  13
4. Circuit Description  19
5. Adjustment Procedure  20
6.  Troubleshooting Flow Chart 54
7. Recommended Spare Parts List 62
8.  Exploded Diagram and Exploded Parts List  64
9. Block Diagram 67
10. Schematic Diagrams 68
11.  PCB Layout Diagrams  74
 
  
						

							
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1. Precautions and Safety Notices 
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 surf ace with sharp or hard objects.   
(8) Do not place heavy objects on the LCD di splay, video cable, or power cord.   
(9) Do not use abrasive cleaners, waxe s 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. Servi ce 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 i s 
exposed in such areas as the a ssociated transformer circuits.   
4. LCD Module 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 CMOS LSI is used in this 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, pr ess 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.   
(11)  After installation of the TFT Module into an enclosure (LCD  monitor 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 Mo dule from outside. Otherwise the TFT 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 for disposal.   
(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 the CCFL to a 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“. 
  
Place the monitor on a clean & soft foam pad .  Place the monitor on foreign objects . 
That could scratch the surface of panel 
  
  
						

							
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2. Specification 
2.1 INSTRUCTION   
FEATURES VX2235wm 
Size  22  wide 
Luminance (Typ)  280 cd/
㎡ 
Contrast Ratio (Typ)  700:1 
Colors  16.2 M    (6 bits + 2 bits FRC) 
Response Time    5 ms(on/off) 
Viewing Angle (H/V)  170 ° / 160 ° 
TFTLCD PANEL 
1
st  
 
CMO 
A220Z1 
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 (NextVision 6)  Yes 
Power Voltage  AC 100-240V, 50/60Hz  Yes 
On Mode(Typ)  < 48 W Power Consumption Off Mode (Max)  ≦
1 W 
Audio    3W / THD 10% (Max)  Yes 
Tilt ( 20  ° - -5  °)  Ye s  
Swivel No 
Pivot No Ergonomics 
Height Adjust  No 
OSD Control  [ 1 ] [ 2 ] [][▼ ] [▲ ] Yes 
Physical (W x H x D)  524 x 482 x 244 mm Dimension 
Package (W x H x D)  575 x 522 x 150 mm 
Physical (Net Weight)  6 Kg / 13.2 lbs We i g h t  
Package (Gross Weight)  7.5 Kg    / 16.5 lbs 
Temperature (℉/℃ ) 41 ℉-95 ℉/+5 ℃-+35 ℃ Operating Condition 
Humidity (%)  20 % - 80 % 
Temperature (℉/℃ ) -4 ℉-131 ℉/-20 ℃-55 ℃ Storage Condition 
Humidity (%)  20 % - 85 % 
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 
VSI: BSMI, CCC, PSB, C-TICK,  MIC, Green Mark 
VSCN:CCC  
						

							
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2.2 GENERAL SPECTION   
 
Test Resolution & Frequency  1680x1050 @ 60Hz 
Test Image Size  Full Size 
Contrast and Brightness Controls  Factory Default:   
Contrast = 70%, Brightness = 100% 
 
2.3 VIDEO INTERFACE 
 
Analog Input Connector  DB-15 (Analog), refer the appendix A 
Digital Input Connector  DVI-D (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 Pin out  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  TTL 
DDC 1/2B  Compliant with Revision 1.3 
Sync Compatibility  Separate Sync, Composite Sync, SOG 
Video Compatibility 
Shall be compatible with all PC ty
pe 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 , 1400 x 1050 , 1440 x 900 , 1600 x 1200, 1680 x 1050 
 
* 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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2.4 POWER SUPPLY 
 
Internal Power Supply  Part Number: 27-D009542  
Input Voltage Range  AC100~240 (Worldwide) 
Input Frequency Range  50    to 60 Hertz 
Short Circuit Protection  OUTPUT CAN BE SHORTED WITHOUT DAMAGE 
Over Current Protection  3.3~4.5A    typical 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  < 48 WATTS (TYP) 
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 powe
r 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) Nois
e measurements of machines 
acoustics. Power Switch noise shall not be considered 
US Type Power Cable    Separate 3-prong NEMA 5-15P type plug.    Length = 1.8m. Connects 
to display. 
Color = Black
 
European Type Power Cable  Schuko CEE7-7 type plug. 
Length = 1.8m, Connects to display.   
Color = Black
 
CCC Type Power Cable    Separate 3-prong type plug.     
Length = 1.8m. Connects to display. 
Color = Black 
PSE Type Power Cable Separate 2-prong NEMA 1-15P type plug.    Length = 1.8m. Connects 
to display. 
Color = Black 
Power Saving Operation(Method)  VESA DPMS Signaling 
Power Consumption On Mode < 48 W (Typ) / 50 W (Max) 
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 
  
						

							
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2.5 ELECTRICAL REQUIREMENT 
Horizontal / Vertical Frequency 
Horizontal Frequency  24 – 82 kHz   
Vertical Refresh Rate 50 – 85* Hz 
Maximum Pixel Clock  150 MHz 
Sync Polarity  Independent of sync polarity.
 
 
 
Timing Table
  
 
Analog 
Item 
Timing 
Separated 
Composite  SOG 
Digital - TMDS 
Remark 
1  640 x 350  @  70  Hz,  31.5  KHz 
　　 　　For Analog sync, the image vertical size image 
will be not full screen (Still 
at the center), And the 
OSD will be 640x350/640x400/720x400 
(primary= 720x400). 
2  640 x 350  @  85  Hz,  37.9  KHz  　　 　　For Analog sync, the image vertical size image 
will be not full screen (Still 
at the center), And the 
OSD will be 640x350/640x400/720x400 
(primary= 720x400). 
3  640 x 400  @  60  Hz,  31.5  KHz  　　 　　For Analog sync, switch 640x400@60Hz and 
640x480@60Hz by [1]+[2] short cut key (primary 
= 640x480@60Hz) 
4  640 x 400  @  70  Hz,  31.5  KHz 
　　 　　For Analog sync, the image vertical size image 
will be not full screen (Still 
at the center), And the 
OSD will be 640x350/640x400/720x400 
(primary= 720x400). 
5  640 x 400  @  85  Hz,  37.9  KHz  　　 　　For Analog sync, the image vertical size image 
will be not full screen (Still 
at the center), And the 
OSD will be 640x350/640x400/720x400 
(primary= 720x400). 
6  640 x 480  @  50  Hz,  24.7  KHz  　　 　    
7  640 x 480  @  60  Hz,  31.5  KHz  　　 　　For Analog sync, switch 640x400@60Hz and 
640x480@60Hz by [1]+[2] short cut key (primary 
= 640x480@60Hz) 
8  640 x 480  @  67  Hz,  35  KHz 
　　 　　  
9  640 x 480  @  72  Hz,  37.9  KHz  　　 　　   
						

							
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10  640 x 480  @  75  Hz,  37.5  KHz  　　 　　  
11  640 x 480  @  85  Hz,  43.3  KHz  　　 　　  
12  720 x 400  @  70  Hz,  31.5  KHz  　　 　　For Analog sync, the image vertical size image 
will be not full screen (Still 
at the center), And the 
OSD will be 640x350/640x400/720x400 
(primary= 720x400). 
13  720 x 400  @  85  Hz,  37.9  KHz  　　 　　For Analog sync, the image vertical size image 
will be not full screen (Still 
at the center), And the 
OSD will be 640x350/640x400/720x400 (primary 
= 720x400). 
14  720 x 480  @  60  Hz,  31.5  KHz  　　 　　For Analog sync, the image vertical size image 
will be not full screen (Still at the center),and the 
information OSD shows 640x480 
15  720 x 576  @  50  Hz,  31.3  KHz 
　　 　　For Analog sync, the image vertical size image 
will be not full screen (Still at the center),and the 
information OSD shows 800x600 
16  800 x 600  @  56  Hz,  35.1  KHz 
　　 　　  
17  800 x 600  @  60  Hz,  37.9  KHz  　　 　　  
18  800 x 600  @  72  Hz,  48.1  KHz  　　 　　  
19  800 x 600  @  75  Hz,  46.9  KHz  　　 　　  
20  800 x 600  @  85  Hz,  53.7  KHz  　　 　　  
21  832 x 624  @  75  Hz,  49.7  KHz  　　 　　  
22  1024 x 768  @  50  Hz,  39.6  KHz  　　 　　For Analog sync, Switch 1024x768@50Hz and 
1280x768@50Hz by [1]+[2] short cut key 
(primary = 1024x768@50Hz) 
23  1024 x 768  @  60  Hz,  48.4  KHz 
　　 　　  
24  1024 x 768  @  70  Hz,  56.5  KHz  　　 　　  
25  1024 x 768  @  75  Hz,  60  KHz  　　 　　  
26  1024 x 768  @  75  Hz,  60.2  KHz  　　 　　  
27  1024 x 768  @  85  Hz,  68.7  KHz  　　 　　  
28  1152 x 864  @  75  Hz,  67.5  KHz  　　 　　  
29  1152 x 870  @  75  Hz,  68.7  KHz  　　 　　  
30  1280 x 768  @  50  Hz,  39.6  KHz  　　 　　For Analog sync, Switch 1024x768@50Hz and 
1280x768@50Hz by [1]+[2] short cut key 
(primary = 1024x768@50Hz) 
31  1280 x 768  @  60  Hz,  47.4  KHz 
　　 　　  
32  1280 x 768  @  60  Hz,  47.8  KHz  　　 　　  
33  1280 x 768  @  75  Hz,  60.3  KHz  　　 　　For Analog sync, Switch 1024x768@75Hz and 
1280x768@75Hz by [1]+[2] short cut key 
(primary = 1024x768@75Hz) 
34  1280 x 768  @  85  Hz,  68.6  KHz 
　　 　　For Analog sync, Switch 1024x768@85Hz and