ViewSonic VA503b-1,VA503m-1,VS11248 Service manual

Service Manual

ViewSonic VA503b-1

VA503m-1

Model No. VS11248

15” Color TFT LCD Display

(VA503b-1_ VA503m-1_SM Rev. 1c Nov. 2006)

ViewSonic 381 Brea Canyon Road, Walnut, California 91789 USA – [phone]

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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 05/10/2006 Initial Release Jamie Chang

1b 08/01/2006 VS-E060194 Add 2nd panel source( HSD A02) Jamie Chang

1c 11/17/2006 VS-E060417 Add SVA NEC XG04 TB panel source Jamie Chang

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TABLE OF CONTENTS

1. Precautions and Safety Notices 1

2. Specification 4

3. Front Panel Function Control Description 13

4. Circuit Description 19

5. Adjustment Procedure 26

6. Troubleshooting Flow Chart 50

7. Recommended Spare Parts List 51

8. Exploded Diagram and Exploded Parts List 57

9. Block Diagram 67

10. Schematic Diagrams 68

11. PCB Layout Diagrams 75

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1. Precautions and Safety Notices

1.1 SAFETY PRECAUTIONS

This monitor is manufactured and tested on a ground principle that a user’s safety comes
first. However, improper use or installation may cause damage to the monitor as well as
the user. Carefully go over the following WARNINGS before installing and keep this guide
handy.

WARNINGS

．This monitor should be operated only at the correct power sources indicated on the label

on the rear end of the monitor. If you’re unsure of the power supply in your residence,
consult you local dealer or power company.

．Use only the special power adapter that comes with this monitor for power input.

．Do not try to repair the monitor your self as it contains no user-serviceable parts. This

monitor should only be repaired by a qualified technician.

．Do not remove the monitor cabinet. There is high-voltage parts inside that may cause

electric shock to human bodies, even when the power cord is unplugged.

．Stop using the monitor if the cabinet is damaged. Have it checked by a service technician.
．Put your monitor only in a clean, dry environment. If it gets wet, unplug the power cable

immediately and consult your service technician.

．Always 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.

．Keep the monitor away from magnetic objects, motors, TV sets, and transformer.
．Do not place heavy objects on the monitor or power cord.

1.2 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 voltages, 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.

1.3 SERVICE NOTES

1. When replacing parts or circuit boards, clamp the lead wires around terminals before
soldering.

2. When replacing a high wattage resistor(more than 1W of metal oxide film resistor) in
circuit board, keep the resistor about 5mm away from circuit board.

3. Keep wires away from high voltage, high temperature components and sharp edges.

4. Keep wires in their original position so as to reduce interference.

5. Usage of this product please refer to also user’s manual.

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1.4 HANDING AND PLACING METHODS

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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 polarizer.

Surface of the LCD panel is pressed by fingers
and that may cause “Mura.”

Take out the monitor with cushions

Taking out the monitor by grasping the LCD
panel. That may cause “Mura.”

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Place the monitor on a clean and soft foam

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pad.

Place the monitor on the lap, the panel
surface must be upwards.

Placing 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

INTRODUCTION

FEATURES VA503b / VA503m
Size 15 “
Luminance (Typ)

Contrast Ratio (Typ) 500:1

1st TFT LCD panel

2nd TFT LCD panel

3rd TFT LCD panel

4th TFT LCD panel

Input Signal

Sync Compatibility

Compatibility

Power Voltage AC 100-240V, 50/60Hz Yes

Power Consumption

Ergonomics

OSD Control [ 1 ] [ 2 ] [ ][▼] [▲] Yes

Dimension

Weight

Operating Condition

Storage Condition

Regulation

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Colors 16.2 M colors (6+2bit panel)
Response Time (Typ) 12 ms
Viewing Angle (H/V) 120 ° / 100 °
Recommend resolution 1024 x 768 @60Hz

Size 15 “
Luminance (Typ)

Contrast Ratio (Typ) 500 :1
Colors 16.2 M colors (6+2bit panel)
Response Time (Typ) 12 ms
Viewing Angle (H/V) 140 ° / 120 °
Recommend resolution 1024 x 768 @60Hz

Size 15 “
Luminance (Typ)

Contrast Ratio (Typ) 500:1
Colors 16.2 M colors (6+2bit panel)
Response Time (Typ) 12 ms
Viewing Angle (H/V) 120 ° / 100 °
Recommend resolution 1024 x 768 @60Hz

Size 15 “
Luminance (Typ)

Contrast Ratio (Typ) 450:1
Colors 16.2 M colors (6+2bit panel)
Response Time (Typ) 16 ms
Viewing Angle (H/V) 120 ° / 100 °
Recommend resolution 1024 x 768 @60Hz

Analog (75ohms, 0.7/1.0 Vp-p) Yes
Digital (DVI-D) No
Separate Sync Yes
Composite Sync No
Sync on Green No
PC Yes
Power Mac Yes
TV Box (NextVision 6) Yes

On Mode(Max / Typ) Under 23 W in max
Active Off Mode (Max) Saving mode< 2W / Off mode <1 W

Tilt ( -5 ° - 22.5 °)

Swivel No
Pivot No
Height Adjust No

Physical (W x H x D) 344 x 347.5 x 147 (mm)

13.15 x 13.68 x 5.79 (in)

Package (W x H x D) 396 x 400 x 141 (mm)

Physical (Net Weight) 2.7 kg / 5.95 lbs
Package (Gross Weight) 3.7 kg / 8.16 lbs
Temperature (℉/℃) 32℉~104℉ / 0℃~40℃
Humidity (%) 20 % - 90 %
Temperature (℉/℃) -4℉~140℉ / -20℃~60℃
Humidity (%) 5 % - 90 %
CB / TCO99 / UL/cUL / FCC-B / ICES 003 / Argentina-TUV/S / NOM / EPA Energy Star /
TUV/Ergo / ISO134062 / TUV/GS / CE / GOST-R / SASO / BSMI / PSB / C-Tick / CCC / RoHS

/ WEEE

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250 cd/㎡

200 cd/㎡

250 cd/㎡

250 cd/㎡

Yes

15.59 x 15.75 x 5.55 (in

1 GENERAL specification

Test Resolution & Frequency 1024 x 768 @ 60Hz
Test Image Size Full Size

Contrast and Brightness Controls

Factory Default:
Contrast = 70%, Brightness = 100%

2 VIDEO INTERFACE

Analog Input Connector DB-15 (Analog), refer the appendix A
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
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 LVDS
DDC 1/2B Compliant with Revision 1.3
Sync Compatibility Separate Sync

Shall be compatible with all PC type computers,
Video Compatibility

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
Exclusions Not compatible with interlaced video

3 POWER SUPPLY

Internal Power Supply Part Number: 715G1823-I
Input Voltage Range 100 TO 240 VAC
Input Frequency Range 50 TO 60 HERTZ
Short Circuit Protection Output can be shorted without damage
Over Current Protection (1)13V_4.5A@5V_1.5A

(2)5V_6A@13V_2A
Leakage Current 3.5 mA (Max) at 254VAC / 60Hz
Efficiency 80 % typical at 115VAC Full Load

Fuse Internal and not user replaceable
Power Dissipation 4 Watts (typ)
Max Input AC Current 1 Arms @ 90VAC, 0.5 Arms @180VAC
Inrush Current (Cold Start) 60 A @ 240 VAC, 30 A(max) @ 110 VAC

Shall start and function properly when under full load, with
Power Supply Cold Start

all combinations of input voltage, input frequency, and

operating temperature

Power Supply Transient Immunity

Power Supply Line Surge Immunity

Shall be able to withstand an ANSI/IEEE C62.41-1980

6000V 200 ampere ring wave transient test with no damage

Shall be able to withstand 1.5 times nominal line voltage

for one cycle with no damage

Shall be able to function properly, without reset or visible
Power Supply Missing Cycle Immunity

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

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in compliance with ISO 7779 (DIN EN27779:1991) Noise

measurements of machines acoustics. Power Switch noise

shall not be considered
US Type Power Cable Length = 1.8m. Connects to AC/DC Power Color = Black
Power Saving Operation(Method) VESA DPMS Signaling

Power Consumption

ON Mode < 23 W (max)

POWER SAVING < 2W ,OFF < 1W
Recovery Time On Mode = N/A, Active Off < 3 sec

4 ELECTRICAL REQUIREMENT

Horizontal / Vertical Frequency

Horizontal Frequency 30 – 62 KHZ
Vertical Refresh Rate 50 – 85 HZ.
Maximum Pixel Clock 80 MHz
Sync Polarity Independent of sync polarity.

Timing Table

Item Timing Analog

1 640 x 350 @ 70Hz, 31.5kHz

2 640 x 400 @ 70Hz
3 640 x 480 @ 50Hz

4 640 x 480 @ 60Hz, 31.5kHz
5 640 x 480 @ 67Hz, 35.0kHz
6 640 x 480 @ 72Hz, 37.9kHz
7 640 x 480 @ 75Hz, 37.5kHz
8 640 x 480 @ 85Hz, 43.27kHz

9 720 x 400 @ 70Hz, 31.5kHz
10 800 x 600 @ 56Hz, 35.1kHz
11 800 x 600 @ 60Hz, 37.9kHz
12 800 x 600 @ 72Hz, 48.1kHz
13 800 x 600 @ 75Hz, 46.9kHz
14 800 x 600 @ 85Hz, 53.7kHz
15 832 x 624 @ 75Hz, 49.7kHz
16 1024 x 768 @ 60Hz, 48.4kHz
17 1024 x 768 @ 70Hz, 56.5kHz
18 1024 x 768 @ 72Hz, 58.1kHz
19 1024 x 768 @ 75Hz, 60.0kHz

Yes

Yes
Yes

Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes

*1. Tolerance ≧ ± 2kHz.
*2. Any timing not in the list, it should display as normal or show on “OUT OF RANGE” OSD message

without blanking.

*3. The image quality of 85Hz mode might be worse than 75Hz.

AUDIO INTERFACE (SPEAKER SPECIFICATION) (For VA503m only)
Line input connection 3.5 mm stereo jack
Line input signal 1.0Vrms
Line input impedance >10 kOhm

Maximum power output (Electric) 1 W @ < 8% distortion

Signal to Noise Ratio 50 dB
Frequency response 500 Hz – 20 Khz
Distortion < 8 % THD (@1kHz)

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Vibration

Screen image

There should be no audible vibration with volume at
100%. (Input signal within 1.0 Vrms)
There should be no affect on the screen image stability

under any conditions
Connector PC99 requirement Audio in Lime Green pantone # 577C
Cable type / length 3.5mm stereo cable / 1.8m length

Audio DPMS

Note: There is no guarantee <1 W power consumption in

Active Off mode, when the Audio Cable is connected

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TFT LCD PANEL

1st Panel Source HSD 150MX17 A01
Type TN, LVDS
Active Size 304.1 mm (H) x 228.1mm (V)
Pixel Arrangement RGB Vertical Stripe
Pixel Pitch 0.297 mm
Glass Treatment Anti Glare (Hard coating 3H)
# of Backlights 2 CCFL edge-light
Backlight Life 30,000 Hours (Min)
Luminance –Condition: CT = 6500 K

Contrast = Max, Brightness = Max

250 cd/m2 (Typ after 30 minute warm up)

200 cd/m2 (Min after 30 minute warm up)
Brightness Uniformity 75 % (min)
Contrast Ratio 500 :1 (Typ), 400 :1 (Min)
Color Depth Vertical) 16.2 million colors (6+2 bit panel)
Viewing Angle (Horizontal)
Viewing Angle (Vertical)
Response Time

10%-90% @ Ta=25°C

120° (Typ)@ CR>10 / X° (Typ)@ CR>5

100° (Typ) @ CR>10 / X° (Typ)@ CR>5

12 ms (Tr= 8.5 ms, Tf = 3.5 ms) (Typ)

18 ms (Tr= 5 ms, Tf = 11 ms) (max)
Panel Defects Please see Panel Quality Specifications.

2nd Panel Source AUO, M150XN07 v3
Type TN, LVDS
Active Size 304.128 mm (H) x 228.096mm (V)
Pixel Arrangement RGB Vertical Stripe
Pixel Pitch 0.297 mm
Glass Treatment Anti Glare (Hard coating 3H)
# of Backlights 2 CCFL edge-light
Backlight Life 30,000 Hours (at 8.0mA)
Luminance –Condition: CT = 6500 K

Contrast = Max, Brightness = Max

200 cd/m2 (Typ after 30 minute warm up)

150 cd/m2 (Min after 30 minute warm up)
Brightness Uniformity 80%(typ) / 75 % (min)
Contrast Ratio 500 :1 (Typ), 400 :1 (Min)
Color Depth Vertical) 16.2 million colors (6+2 bit panel)
Viewing Angle (Horizontal) 140° (Typ)@ CR>10 / 140° (Typ)@ CR>5
Viewing Angle (Vertical) 120° (Typ) @ CR>10 / 130° (Typ)@ CR>5
Response Time

10%-90% @ Ta=25°C

12 ms (Tr= 8.5 ms, Tf = 3.5 ms) (Typ)

16 ms (Tr= 11 ms, Tf = 5 ms) (max)
Panel Defects Please see Panel Quality Specifications.

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3rd Panel Source HSD 150MX17 A02
Type TN, LVDS
Active Size 304.1 mm (H) x 228.1mm (V)
Pixel Arrangement RGB Vertical Stripe
Pixel Pitch 0.297 mm
Glass Treatment Anti Glare (Hard coating 3H)
# of Backlights 2 CCFL edge-light
Backlight Life 30,000 Hours (Min)
Luminance –Condition: CT = 6500 K

Contrast = Max, Brightness = Max

250 cd/m2 (Typ after 30 minute warm up)

200 cd/m2 (Min after 30 minute warm up)
Brightness Uniformity 75 % (min)
Contrast Ratio 500 :1 (Typ), 400 :1 (Min)
Color Depth Vertical) 16.2 million colors (6+2 bit panel)
Viewing Angle (Horizontal)
Viewing Angle (Vertical)
Response Time

10%-90% @ Ta=25°C

120° (Typ)@ CR>10 / X° (Typ)@ CR>5

100° (Typ) @ CR>10 / X° (Typ)@ CR>5

12 ms (Tr= 8.5 ms, Tf = 3.5 ms) (Typ)

18 ms (Tr= 5 ms, Tf = 11 ms) (max)
Panel Defects Please see Panel Quality Specifications.

4th Panel Source SVA 150XG04TB
Type TN, LVDS
Active Size 304.1 mm (H) x 228.1mm (V)
Pixel Arrangement RGB Vertical Stripe
Pixel Pitch 0.297 mm
Glass Treatment Anti Glare (Hard coating 3H)
# of Backlights 2 CCFL edge-light
Backlight Life 30,000 Hours (Min)
Luminance –Condition: CT = 6500 K

Contrast = Max, Brightness = Max

250 cd/m2 (Typ after 30 minute warm up)

200 cd/m2 (Min after 30 minute warm up)
Brightness Uniformity 75 % (min)
Contrast Ratio 450 :1 (Typ), 350 :1 (Min)
Color Depth Vertical) 16.2 million colors (6+2 bit panel)
Viewing Angle (Horizontal)
Viewing Angle (Vertical)
Response Time

10%-90% @ Ta=25°C

120° (Typ)@ CR>10 / X° (Typ)@ CR>5

100° (Typ) @ CR>10 / X° (Typ)@ CR>5

16 ms (Tr= 4 ms, Tf = 12 ms) (Typ)

25 ms (Tr= 7 ms, Tf = 18 ms) (max)
Panel Defects Please see Panel Quality Specifications.

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IMAGE PERFORMANCE

Display Size
Horizontal Display Size, Primary Preset Full Screen
Vertical Display Size, Primary Preset Full Screen

Preset Color Temperatures

sRGB

It should meet IEC 61966-2-1 (1999-10) standard.

Preset 1(9300K)
CCT(Max) = 10250K
CCT(Min) = 8500K

Preset 2 (Primary)(6500K)
CCT(Max) = 7595K
CCT(Min) = 5930K

Preset 3(5400K)
CCT(Max) = 5830K
CCT(Min) = 4860K

Preset Color Temperature

CCT (typ) = 9300K (u’CCT=0.1888; v’ CCT=0.4457)

CCT (max) = 10250K, CCT (min) = 8500K

Δu’v’<0.01 (@ Full White pattern)

CCT (typ) = 6500K (u’CCT=0.1978; v’ CCT=0.4684)

CCT (max) = 7595K, CCT (min) = 5930K

Δu’v’<0.01 (@ Full White pattern)

CCT (typ) = 5400K (u’CCT=0.2044; v’ CCT=0.4808)

CCT (max) = 5830K, CCT (min) = 4860K

Δu’v’<0.01 (@ Full White pattern)

Each color preset shall be adjustable. Red, Green, and Blue
shall be individually controlled.

Video Cards Compatibility
Peaking Performance: Peaking is not adjustable

Raster Artifacts

● Video Artifacts : No visible streaking, sag, or smearing artifacts when driven by the specified video

cards in the primary mode and after user adjustment to best condition

● Power Supply, and Grounding Artifacts : No visible artifacts in any specified video mode within the

horizontal or vertical frequency range of the monitor

Temperature Drift : Image shall not drift or lose fine-tune adjustment

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MECHANICAL

Dimension

Dimension (Desktop) 344mm(W)*347.5mm(H)*147mm(D)
Width 344mm
Height (Height adjust to the bottom) 347.5mm
Depth 147mm
Monitor Weight 2.7Kg(N/W); 3.7Kg(G/W)
*Refer to Figure 1
Dimension (Head Only / Wall Mount) 344mm (W)*290mm(H)*54mm(D)
Width 344mm
Height 290mm
Depth 54mm
Monitor Weight 2.4Kg
*Refer to Figure 1

Ergonomics

Tilt Up step 1 0° to 20°±2.5°

Tilt Down N/A
Swivel Right N/A
Swivel Left N/A
Height Adjust N/A
Pivot N/A

Cabinet Material
Display Head Plastic Material Samsung starex ABS SD-0150 (94HB)
Neck/Base Plastic Material Samsung starex ABS SD-0150 (94HB)

Internal Plastic Cabinet Components

All internal plastic cabinet components shall be in

compliance with the requirements of TCO99

The reference for the bezel is the silver color

Front Bezel Color

(VA503m) and the midnight gray color (VA503b)
chip provided by ViewSonic
The reference for the bezel is the black color
(VA503m) and the midnight gray color
(VA503b) chip provided by ViewSonic.

Neck, Base, and Rear Cover Color

The color difference between any two cabinet

components shall be less than 0.80 “Delta E”,

in the 1976 CIE L*a*b Colorspace.

Rear logo color Mold type

The color drift due to UV-Light shall be less than 3.0

Cabinet Color Drift Due To UV-Light

“Delta E” in the 1976 CIE L*a*b colorspace.
Testing shall be performed according to the
requirements of ASTM Test Method D4459-93.

Cabinet Texture

Mold-Tech # 11010 used on all external textured
surfaces.
The supplier shall submit textured color chips, plastic

Samples

material specifications, and Material Safety Data
Sheets for approval.

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INTERFACE DESCRIPTION

D-SUB 15 PIN CONNECTOR

15
6

11 15

10

SIGNAL LEVEL

Pin Number Pin Function

1 Red video input
2 Green video input
3 Blue video input
4 No Connection
5 Ground
6 Red video ground
7 Green video ground
8 Blue video ground

9 +5V
10 H/V sync ground
11 No connection
12 (SDA)
13 Horizontal sync (Composite sync)
14 Vertical sync
15 (SCL)

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3. Front Panel Function Control Description

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Do the following to adjust the display setting:

1. To display the Main Menu, press button [1].

NOTE: All OSD menus and adjustment screens disappear automatically after about 15

seconds. This is adjustable through the OSD timeout setting in the setup menu.

2. To select a control to adjust, press ▲or ▼ to scroll up or down in the Main Menu.

3. After the desired control is selected, press button [2]. A control screen like the one

shown below appears.

The line at the bottom of the screen shows the
current functions of buttons 1 and 2: Exit or
select the Brightness control.

4. To adjust the control, press the up ▲ or▼ down T buttons.

5. To save the adjustments and exit the menu, press button [1] twice.
The following tips may help you optimize your display:

• Adjust the computer's graphics card so that it outputs a 1024 x 768 @ 60Hz video
signal to the LCD display. (Look for instructions on “changing the refresh rate” in the
graphics card's user guide.)

• If necessary, make small adjustments using H. POSITION and V. POSITION until the
screen image is completely visible

. (The black border around the edge of the screen

should barely touch the illuminated “active area” of the LCD display.)

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Main Menu Controls

Adjust the menu items shown below by using the up S and down T buttons.

Control Explanation

Auto Image Adjust automatically sizes, centers, and fine tunes the video signal
to eliminate waviness and distortion. Press the [2] button to obtain a sharper
image.

NOTE: Auto Image Adjust works with most common video cards. If this
function does not work on your LCD display, then lower the video refresh rate
to 60 Hz and set the resolution to its pre-set value.

Contrast adjusts the difference between the image background (black level)
and the foreground (white level).

Brightness adjusts background black level of the screen image.

Audio Adjust（For VA503m only）
Volume increases the volume, decreases the volume, and mutes the audio.
Mute temporarily silences audio output.

Color Adjust provides several color adjustment modes, including preset color
temperatures and a User Color mode which allows independent adjustment of
red (R), green (G), and blue (B). The factory setting for this product is 6500K
(6500 Kelvin).

sRGB-This is quickly becoming the industry standard for color management,
with support being included in many of the latest applications. Enabling this
setting allows the LCD display to more accurately display colors the way they
were originally intended. Enabling the sRGB setting will cause the Contrast and
Brightness adjustments to be disabled.

9300K-Adds blue to the screen image for cooler white (used in most office
settings with fluorescent lighting).

6500K-Adds red to the screen image for warmer white and richer red.

5400K-Adds green to the screen image for a darker color.

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Control Explanation

User Color Individual adjustments for red (R), green (G), and blue (B).

1. To select color (R, G or B) press button [2].

2. To adjust selected color, pressSandT.

Important: If you select RECALL from the Main Menu when the product is

set to a Preset Timing Mode, colors return to the 6500K factory preset.

Information displays the timing mode (video signal input) coming from the
graphics card in the computer, the LCD model number, the serial number, and
the ViewSonic® website URL. See your graphics card’s user guide for
instructions on changing the resolution and refresh rate (vertical frequency).

NOTE: VESA 1024 x 768 @ 60Hz (recommended) means that the resolution is
1024 x 768 and the refresh rate is 60 Hertz.

Manual Image Adjust displays the Manual Image Adjust menu.

H. Size (Horizontal Size) adjusts the width of the screen image.

H./V. Position (Horizontal/Vertical Position) moves the screen image left or

right and up or down.

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Control Explanation

Fine Tune sharpens the focus by aligning text and/or graphics with pixel

boundaries.

NOTE: Try Auto Image Adjust first.

Sharpness adjusts the clarity and focus of the screen image.

Setup Menu displays the menu shown below:

Language Select allows the user to choose the language used in the menus and

control screens.

Resolution Notice displays the Resolution Notice menu shown below.

Resolution Notice advises the optimal resolution to use.

OSD Position allows the user to move the OSD menus and control screens.

OSD Timeout sets the length of time the OSD screen is displayed. For example,

with a “15 second” setting, if a control is not pushed within 15 seconds, the
display screen disappears.

OSD Background allows the user to turn the OSD background On or Off.

Memory Recall returns the adjustments back to factory settings if the display is

operating in a factory Preset Timing Mode listed in the Specifications of this
manual.
Exception: This control does not affect changes made with the User Color
control, Language Select or Power Lock setting.

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SHORT CUTS FUNCTION FROM THE BUTTONS

[1]

Main Menu

[2]

[▼] or [▲]

[▼] + [▲]

[1] + [2]

[1] + [▼] + [▲]

(keep pushing 5 sec)

[1] + [▼]
[1] + [▲]

Auto Image Adjust
To immediately activate Contrast menu. It should be

change to Brightness OSD by push button [2]
recall both of Contrast and Brightness to default
toggle 720x400 and 640x400 mode when input 720x400

or 640x400 mode
White Balance (Not shown on user’s guide)

Power Lock
OSD Lock

Remark : All the short cuts function are only available while OSD off

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4. Circuit Description

4.1 LCD MONITOR DESCRIPTION

The LCD MONITOR will contain a Main Board, an Power Board, Key Board which

house the flat panel control logic, brightness control logic and DDC.

Monitor Block Diagram

Power Board

(Include: adapter, inverter)

AC-IN

100V-240V

4.2 MAIN BOARD BLOCK FUNCTION DESCRIPTION

The main board contains panel control logic, brightness control logic, DDC and DC

convert DC circuit and so on.

R
G
B
H

V
SDA
SCL

CCFL Drive.

Main Board

Key Board

EPROM EPROM

Flat Panel and
CCFL backlight

HOST Computer

PWPC board

TSUM16AK

OSC

RS232 Connector
For white balance
adjustment in factory
mode

Video signal, DDC

Backlight and Panel

Keyboard

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4.3 PWPC BOARD BLOCK FUNCTION DESCRIPTION

PWPC board combines to adapter and inverter, Adapter which commonly consists
of bridge rectifier and filter, start circuit, PWM control circuit, protection circuits and
convert to 12V, 5V DC voltage by input 90V-240V AC voltage that provide power supply
for each chips in the main board and inverter. Inverter is DC TO AC circuit. It changes
the 12v DC of power supply to about 600-800v AC that drives the backlight. It mostly
consists of starting circuit, PWM controller, DC changing circuit, LC surging circuit,
output circuit and protection circuit etc.

AC input

EMI filter

Bridge
Rectifier
and Filter

Transformer

Rectifier
CMOS

St art Circuit
R903, R904,R905

5V

Lamp

OSC and
Output
Circuit

Feedback
Circuit

PWM

Control IC

Over
Voltage

DC Convert
Circuit

MOSFET
Q203

PWM
Control IC

Over
Voltage
Protect

12V

ON/OF

ON/OFF
Control

DIM

CN902

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4.4 INTRODUCTION OF IC

STUM16AK(U401): integrate ADC, OSD, SCALER, MCU, LVDS, convert analog RGB

into digital and room and shrink scaling output to LCD panel.

PIN Function:

Pin Symbol Description

70 SDO SPI flash serial data output; Input w/5V-tolerant
71 CSZ SPI flash chip select; output
72 SCK SPI flash serial select; output
73 SDI SPI flash serial data input; output
65 DDCA_SDA/RS232_TX DDC data for analog interface; 4mA driving

strength/UART transmitter/GPIO; I/O w/5V-tolrant

66 DDCA_SDA/RS232_RX DDC data for analog interface/UART

transmitter/GPIO;Input w/5V-tolrant
19 RST Chip reset; High reset; Input w/5V-tolerant
22 RSTN Chip reset; Low reset; Input w/5W-toerant

11 VCTRL Regulator control; Output
63 HSYNCO Analog HSYNC input
64 VSYNCO Analog VSYNC input
62 REFP Internal ADC top de-coupling pin
61 REFM Internal ADC bottom de-coupling pin
51 REXT

External resistor 390 ohm to AVDD＿ADC
21 PWM1 PWM1; 4mA driving strength; Output
29 PWM0 PWM0; 4mA driving strength; Output

4 BYPASS For External Bypass Capacitor
32 XIN Xin; Crystal Oscillator Input
33 XOUT Xout; Crystal Oscillator Output

44、50、60 AVDD＿ADC

52
34

14、67、95、

103、115

12、68、97、

AVDD＿PLL

AVDD＿MPLL

VDDP Digital Output Power 3.3V
VDDC Digital Core Power 1.8V

ADC Power 3.3V
PLL Power 3.3V
MPLL Power 3.3V

117

AIC1084-33PM (U702): DC power convert, used to 5v convert 3.3v.
LT1117-18(U701): DC power convert, used to 5v convert 3.3v.
TPA3003D2 (U601): The TPA3003D2 is a audio amplifier IC,3-W efficient, driving

speakers as low as 8

, range of gain from -40dB to 36 dB. The function of

each pin and the inside circuit diagram are as follows:

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Circuit Diagram

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PIN Function

TERMINAL

NO. NAME

I/O DESCRIPTION

AGND 9,10,26 ­AVcc 33 ­AVDD 29 O
AVDDREF 7 O
BSLN 13 I/O
BSLP 24 I/O
BSRN 48 I/O
BSRP 37 I/O

COSC 28 I/O

FADE 30 I

LINN 6 I
LINP 5 I
LOUTN 16,17 O
LOUTP 20,21 O
MUTE 34 I
NC 31,32,35 ­PGNDL 18,19 ­PGNDR 42,43 -

PVVCCL 14,15 ­PVVCCL 22,23 ­PVCCR 38,39 ­PVCCR 46,47 ­REFGND 12 -

RINP 3 I
RINN 2 I
ROSC 27 I/O
ROUTN 44,45 O
ROUTP 40,41 O

SD 1 I

VCLAMPL 25 ­VCLAMPR 36 ­VOLUME 11 I
VREF 8 I

V2P5 4 O

Analog gr ound for digital/analog cells in core
High-voltage analog power supply (8.5V to 14V)
5-V Regulated output
5-V Reference output-provided for connection to adjacent VREF terminal.
Bootstrap I/O for left channel, negative high-side FET
Bootstrap I/O for left channel, positive high-side FET
Bootstrap I/O for right channel, negative high-side FET
Bootstrap I/O for right channel, positive high-side FET
I/O for charge/discharging currents onto capacitor for ramp generator triangle wave

biased at V 2P 5
Input for controlling volume ramp rate when cycling SD or during power-up. A logic
low on this pin places the amplifier in fade mode. A logic
high on this pin allows a quick transition to the desired volume setting.
Negative differential audio input for left channel

Positive differential audio input for left channel
Class-D 1/2-H-bridge negative output for left channel
Class-D 1/2-H-bridge positive output for left channel
A logic high on this pin disables the outputs. A low on this pin enables the outputs.
Not internally connected
Power ground for left channel H-bridge
Power ground for right channel H-bridge
Power supply for left channel H-bridge(tied to pins 22 and 23 internally), not

connected to PVCCR or AVcc
Power supply for left channel H-bridge(tied to pins 14 and 15 internally), not
connected to PVCCR or AVcc
Power supply for right channel H-bridge(tied to pins 46 and 47 internally), not
connected to PVCCL or AVcc
Power supply for right channel H-bridge(tied to pins 38 and 39 internally), not
connected to PVCCL or AVcc
Ground for gain control circuitry. Connect to AGND. If using a DAC to control the
volume, connect the DAC ground to this terminal.
Positive differential audio input for right channel

Negative differential audio input for right channel
Current setting resistor for ramp generator. Nominally equal to 1/8*Vcc
Class-D 1/2-H-bridge negative output for right channel
Class-D 1/2-H-bridge positive output for right channel
Shutdown signal for IC (low=shutdown, high=operational). TTL logic levels with

compliance to Vcc.
Internally generated voltage supply for left channel bootstrap capacitors.

Internally generated voltage supply for right channel bootstrap capacitors.
DC voltage that sets the gain of the amplifier.
Analog reference for gain control section.

2.5-V Reference for analog cells, as well as reference for unused audio input when
using single-ended inputs.

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