ViewSonic VX715 - 17" LCD Monitor User manual

Service Manual
ViewSonic VX715
Model No VS10057
17” Color TFT LCD Display
Manufacture Date: Jan-10-05

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2
Copyright
Copyright@ 2004 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 manual or otherwise, without the
prior written permission of ViewSonic Corporation.
Disclaimer
ViewSonic makes no representation or warranties, either expressed or implied, with respect to the contents hereof and
specifically disclaims any warranty of merchantability of 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 trademark used within this document is the property of their respective owners.
Revision History
Revision Date Description of changes Approval
A00 Jan-10-05 Initial Release

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TABLE OF CONTENTS
1. Precautions and Safety Notices 4
2. Specification 5
3. Front Panel Function Control Description 8
4. Function Module Description 14
5. Adjusting Produce 20
6. Trouble Shooting Flow Chart 28
7. Recommended Spare Parts List 34
8. Exploded Diagram and Spare Parts List 45
9. Block Diagram 47
10. Schematic Diagram 48
11. PCB Layout Diagram 53

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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
zThis 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.
zUse only the special power adapter that comes with this monitor for power input.
zDo not try to repair the monitor yourself as it contains no user-serviceable parts. This monitor should only be
repaired by a qualified technician.
zDo not remove the monitor cabinet. There is a high-voltage part inside that may cause electric shock to human
bodies, even when the power cord is unplugged.
zStop using the monitor if the cabinet is damaged. Have it checked by a service technician.
zPut your monitor only in a clean, dry environment. If it gets wet, unplug the power cable immediately and consult
your service technician.
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.
zKeep the monitor away from magnetic objects, motors, TV sets, and transformer.
zDo 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 refers to also user’s manual.

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2. Specification
2.1 PRODUCT SPECIFICATIONS
LCDPanel 17.0”TFT
PowerManagement EnergyStarcompliantVESA
DPMScompatible
<1W
Recommend Resolution 1280 x1024@60Hz
PixelDimension 0.264(H)x0.264(V)mm
LCDDisplayColor 16.2MColors(6+2FRCbit)
ViewingAngle Horizontal:140deg
Vertical:130deg
ContrastRatio 450：1 (Typ.)
Brightness 300cd/㎡(Typ.)
ResponseTime Tr:6ms Tf:10ms(Typ.)
Active Display Area 337.920(H) x 270.336(V)
Temperature Operating:0°Cto+40°C
Storage:-20°Cto+60°C
Power InputVoltage:90V~264V
Consumption:35Watts(Max.) 32Watts(Typ.)
2.2 FACTORY SUPPORTING MODES
Primary Preset: VESA: 1280 x1024@60Hz
Timing Table: 1. 640 x 350 @ 70Hz, 31.5kHz
2. 640 x 400 @ 60Hz, 31.5kHz
3. 640 x 400 @ 70Hz, 31.5kHz
4. 640 x 480 @ 50Hz, 24.7kHz
5. 640 x 480 @ 60Hz, 31.5kHz
6. 640 x 480 @ 67Hz, 35.0kHz
7. 640 x 480 @ 72Hz, 37.9kHz
8. 640 x 480 @ 75Hz, 37.5kHz
9. 640 x 480 @ 85Hz, 43.27kHz
10. 720 x 400 @ 70Hz, 31.5kHz
11. 800 x 600 @ 56Hz, 35.1kHz
12. 800 x 600 @ 60Hz, 37.9kHz
13. 800 x 600 @ 75Hz, 46.9kHz
14. 800 x 600 @ 72Hz, 48.1kHz
15. 800 x 600 @ 85Hz, 53.7kHz
16. 832 x 624 @ 75Hz, 49.7kHz
17. 1024 x 768 @ 60Hz, 48.4kHz
18. 1024 x 768 @ 70Hz, 56.5kHz
19. 1024 x 768 @ 72Hz, 58.1kHz
20. 1024 x 768 @ 75Hz, 60.0kHz
21. 1024 x 768 @ 85Hz, 68.67kHz

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22. 1152 x 864 @ 75Hz, 67.5kHz
23. 1152 x 870 @ 75Hz, 68.7kHz
24. 1280 x 1024 @ 60Hz, 63.4kHz
25. 1280 x 1024 @ 75Hz, 79.97kHz
26. 1280x 720 @ 60Hz, 45kHz (HDTV)
2.3D-SUBCONNECTOR
15
610
11 15
D-SUB 15 PIN CONNECTOR
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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DVI 24 PIN CONNECTOR
Pin No. Signal Name Description
1 RX2- TMDS negative differential input, channel 2
2 RX2+ TMDS positive differential input, channel 2
3 GND Logic Ground
4 Reserved 4 Reserved. No connection
5 Reserved 5 Reserved. No connection
6 DDC-CLK DDC2B Clock
7 DDC-DAT DDC2B Data
8 Reserved 8 Reserved. No connection
9 RX1- TMDS negative differential input, channel 1
10 RX1+ TMDS positive differential input, channel 1
11 GND Logic Ground
12 Reserved 12 Reserved. No connection
13 Reserved 13 Reserved. No connection
14 VCCX Power
15 GND Logic Ground
16 SENS SENSE Pin, Pull High
17 RX0- TMDS negative differential input, channel 0
18 RX0+ TMDS positive differential input, channel 0
19 GND Logic Ground
20 Reserved 20 Reserved. No connection
21 Reserved 21 Reserved. No connection
22 GND Logic Ground
23 RXC+ TMDS positive differential input, reference clock
24 RXC- TMDS negative differential input, reference clock

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3. Front Panel Function Control Descriptions
Main Menu
With On View controls
Front Control Panel
Shown below in detail
Display the Main Menu.
or exits the control screen
and saves adjustments
1.Scrolls through menu options
and adjusts displayed control.
2.Also a shortcut to display the
contrast adjustment control screen
1. Display the control screen
for the highlighted control.
2. Also toggles between two
control on some screens
3. Also a shortcut to toggle
between analog and digital
connections.
Power light
Green = ON
Orange = Power Saving
Power
On/Off

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Do the following to adjust the screen image:
1.To display the Main Menu, press button: [1]
NOTE: All On View menus and adjustment screens disappear automatically after about 30 seconds.
2. To select a control you want to adjust, press ▲or ▼to scroll up or down the Main Menu.
3. After the control is selected, press button [2]. A control screen like the one shown below appears.
4. To adjust the control press the up ▲or down ▼buttons.
5. To save the adjustments and exit the menu, press button [1] twice.
The following tips may help you optimize your display:
zAdjust your computer’s graphic card so that is outputs a video signal 1280×1024@60Hz to the LCD display.
zIf 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 is illuminated “active area” of the LCD
display.)

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Main Menu Control
Adjust the menu items shown below by using up ▲or down ▼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 shaper image.
Note: 1. Auto Image Adjust works with most common video card. 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.
2.The Auto Image Adjust and most Manual image Adjust functions are not available for DVI input
Contrast adjusts the different between the image background (black level) and the
fore
g
round
(
white level
)
.
Brightness adjusts background black level of the screen image.
Input Select allow you to toggle between an analog and a digital signal.
Color Adjust provides several color adjustment modes: preset color temperature and RGB which
allow you to adjust red (R), green (G), blue (B) separately. The factory setting for this product is
6500K (6500 Kelvin).
sRGB — sRGB 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 setting with
fluorescent lighting).
6500K — Adds red to the screen image for warmer white (used in most office setting with
fluorescent li
g
htin
g)
.

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5400K — Adds green to the screen image for a darker color.
5000K — Adds blue and green to the screen image for a darker.
User Color — Individual adjustments for red (R), green (G), blue (B).
1. To select color (R, G or B) press button [2].
2. To ad
j
ust selected color,
p
ress ▲or ▼.
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 cards in your computer.
NOTE: VESA 1280×1024@60Hz (recommended) means that the resolution is 1280×1024 and the refresh
rate is 60Hz.
Manual Image Adjust controls are explained below:
Horizontal Position moves the screen image left or right.
Vertical Position moves the screen image up or down.
Horizontal Size adjusts the width of the screen image.
Fine Tune sharpens focus by aligning the illuminated text and or graphic characters.
Sharpness adjusts the clarity and focus of the screen image.

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Setup Menu displays the menu shown below.
The Setup Menu controls are explained below:
Language allows you to choose the language used is the menus and control screens.
Resolution Notice displays the Resolution Notice menu, advises the optimal resolution to use.
OSD Position allows you to move the on-screen display menus and control screens.
OSD Timeout sets the length of time an on-screen display screen is displayed. For
example, with a “15 second” setting, if a control is not pushed within 15 seconds, the
dis
p
la
y
screen disa
pp
ears.
OSD Background allows you to turn the On-Screen-Display background on or off.
Memory Recall returns adjustments to the original factory settings if the display is
o
p
eratin
g
in a factor
y
Preset Timin
g
Mode listed in this user
g
uide.
Exception: This control does not affect changes mode with the User Color
control, Lan
g
ua
g
e and Power Lock settin
g
.

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Short Cut Key
Function key: 5 keys [ 1 ] [▼] [▲] [ 2 ] [ ]
[1] Main Menu
[2] Input toggle (Analog or Digital) or Auto Image Adjust.
[▼] or [▲] to immediately activate Contrast menu. It should be change to Brightness
OSD by push button [2]
[▼]+ [▲] recall both of Contrast and Brightness to default
[1] + [2] toggle 720x400 and 640x400 mode when input 720x400 or 640x400 mode
[1] + [▼] + [▲] White Balance. (Not shown on user’s guide)
[1] + [▼] Power Lock
[1] + [▲] OSD Lock
[2] + [ ] Factory Mode
Remark: All the short cuts function are only available while OSD off

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4.Function Module Description
4.1 LCD MONITOR DESCRIPTION
The LCD MONITOR will contain a Main Board, a Power Board, and Key Board which house the flat panel control
logic, brightness control logic and DDC.
The Power Board will provide AC to DC Inverter voltage to drive the backlight of panel and the Main Board chips each
voltage.
Power Board
(Include: adapter, inverter)
Flat Panel and
CCFL backlight
Main Board
Key Board
RS232 Connector
For white balance
adjustment in factory
mode
HOST Computer
CCFL Drive.
AC-IN
100V-240V
Video signal, DDC
Monitor Block Diagram

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4.2 POWER BLOCK FUNCTION DESCRIPTION
Inverter Block Function

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Power Block Function

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4.3 Description of Main Chips
MCU: main function is power control, OSD control, frequency calculation, RS232 communication and so on.
RTD2523: integrate ADC, OSD, SCALER, TCON, RSDS, LVDS, convert analog RGB into digital and room and shrink
scaling output to LCD panel.
AP1084: DC power convert, used to 5v convert 3.3v.
RT9164: DC power convert, used to 3.3v convert 2.5v.
24C02: EEPROM, is used to save DDC date which contains the basic parameter of facility, supplier, product name,
maximum H-frequency, support resolution and so on.
M24C16: EEPROM, is used to save Auto config data, white balance data, the state of power key and power on counting
data.

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BA9741F: PWM control, voltage range for working: 3.6~35V, Has such functions as short-voltage protection,
Over-voltage protection, over-current protection and etc. The function of each pin is as follows:
PIN NAME FUNCTION PIN NAME FUNCTION
1 CT External timing capacitor 9 VCC Power supply
2 RT External timing resistor 10 2OUT Output 2
3 1IN+
Positive input for error amplifier
1 11 2DTC
Output 2 dead time/soft start
setting
4 1IN-
Positive input for error amplifier
2 12 2FBK Error amplifier 2 output
5 1FBK Error amplifier 1 output 13 2IN+ Positive input for error
amplifier
6 1DTC
Output 1 dead time/soft start
setting 14 2IN-
Positive input for error
amplifier
7 1OUT Output 1 15 SCP Timing latch setting
8 GND Ground 16 REF
Reference voltage output
(2.5v)

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4.4 Panel Control Circuit
The high level output from U104 makes Q107, Q108 break through, and offer 5V to panel when work well. The output is
low level when it’s saving energy state and Q107, Q108 break off, so the panel doesn’t work
C116
0.1uF
R113 0 1/16W
+12V
+12V
Q107
PMBS3904
32
1
R114 NC
+5V
C180
0.1uF
PANEL_POWER
R217
10K 1/16W
+5V
R219
NC
MCU_VCC
U108
AO3401
+3.3V
R216 NC
+
C115
22uF/16V
R220 4.7K 1/16W
R218
10K 1/16W
PANEL_PW
4.5 On/Off /Brightness control circuit
ON/OFF control: When it works well, the outputs are low level, and high in saving energy state.
Brightness control: When it works well, the output PWM pulse from PIN55 of IC101 adjusts the brightness, the smaller
the duty, and the higher the brightness.

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Q101
PMBS3904
32
1
C119
0.1uF
0805
BACKLIGHT
C114
1uF/16V
R101
4.7K 1/16W
R122
4.7K 1/16W
C120
0.1uF
R112
1K 1/16W
R115
10K 1/16W
B
+5V
+5V
BL_ADJ
R119
1K 1/16W
2N3906
BRIGHTNESS
R121
220 1/16W
Q103
PMBS3904
32
1
E
2N3904
BL_ON_OFF
C
5. Adjust Procedures
5.1 ADJUSTMENT CONDITIONS AND PRECAUTIONS
1. Approximately 30 minutes should be allowed for warm up before proceeding.
2. Adjustments should be undertaken only on those necessary elements since most of them have been carefully preset at
the factory.
3. ESD protection is needed before adjustment.
5.2 MAIN ADJUSTMENTS
NO. FUNCTIONS DESIGNATION
1. WhiteBalance FunctionKey
2. GEOMETRY FunctionKey
5.3 ALIGNMENT PROCEDURES
Approximately 30 minutes should be allowed for warm up before proceeding White-Balance adjustment.
1. Adjust of White Balance
1). How to do the Chroma-7120 MEM. Channel setting
A. Reference to chroma 7120 user guide
B. Use “ SC” key and “ NEXT” key to modify xyY value and use “ID” key to modify the TEXT description Following is
the procedure to do white-balance adjust
2). Setting the color temp. You want
A. MEM.CHANNEL9 (9300 color):
9300 color temp. parameter is Wx = 0.283 ±0.03;Wy = 0.298 ±0.03;