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Service Manual
ViewSonic VA712-2
VA712b-2
Model No. VS10901
17" Color TFT LCD Display
(VA712-2_ VA712b-2_SM Rev. 1a Apr. 2006)
ViewSonic 381 Brea Canyon Road, Walnut, California 91789 USA (800) 888-8583
TABLE OF CONTENTS
1. Precautions and Safety Notices 1
2. Specification 4
3. Front Panel Function Control Description 8
4. Circuit Description 14
5. Adjustment Procedure 26
6. Troubleshooting Flow Chart 49
7. Recommended Spare Parts List 50
8. Exploded Diagram and Exploded Parts List 56
9. Block Diagram 60
10. Schematic Diagrams 61
11. PCB Layout Diagrams 69
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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
¡D 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.
¡D Use only the special power adapter that comes with this monitor for power input.
¡D 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.
¡D 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.
¡D Stop using the monitor if the cabinet is damaged. Have it checked by a service technician.
¡D Put your monitor only in a clean, dry environment. If it gets wet, unplug the power cable
immediately and consult your service technician.
¡D 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.
¡D Keep the monitor away from magnetic objects, motors, TV sets, and transformer.
¡D 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 refers to also user's manual.
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1.4 HANDING AND PLACING METHODS
Correct Methods: Incorrect Methods:
Only touch the metal frame of the LCD
Surface of the LCD panel is pressed by fingers
panel or the front cover of the monitor. Do
and that may cause "Mura."
not touch the surface of the polarizer.
Taking out the monitor by grasping the LCD
Take out the monitor with cushions
panel. That may cause "Mura."
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Placing the monitor on foreign objects. That
Place the monitor on a clean and soft foam
could scratch the surface of the panel or cause
pad.
"Mura."
Place the monitor on the lap, the panel The panel is placed facedown on the lap. That
surface must be upwards. may cause "Mura."
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2. Specification
2.1 PRODUCT SPECIFICATIONS
LCD Panel 17.0" TFT
Recommend Resolution 1280 x1024@60Hz
Pixel Dimension 0.264(H) x 0.264(V)mm
LCD Display Color 16.2M Colors (RGB 6-bit+FRC data)
Horizontal: 140 °
Viewing Angle
Vertical: 130 °
Contrast Ratio 500¡G 1 (Typ.)
Brightness 300 cd/¢T (Typ.)
Response Time 8ms(Typ.)
Active Display Area 337.9mm(H) x 270.3mm(V)
Maximum Pixel Clock 135 MHz
Horizontal Frequency 30 82 kHz
Vertical Refresh Rate 50 85 Hz.
Operating: 0°C to +40°C
Temperature
Storage: -20°C to +60°C
Input Signal Analog / Digital
Energy Star compliant VESA
Power Management DPMS compatible
¡Ø 1 W
Input Voltage : 90V~264ACV¡A 50~60Hz(auto switch)
Power
Consumption: 39 Watts(Max.) 36 Watts(Typ.)
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2.2 FACTORY SUPPORTING MODES
Timing Table :
Item Timing Analog Digital
1 640 x 350 @ 70Hz, 31.5kHz Yes Yes
2 640 x 480 @ 60Hz, 31.5kHz Yes Yes
3 640 x 480 @ 67Hz, 35.0kHz Yes Yes
4 640 x 480 @ 72Hz, 37.9kHz Yes Yes
5 640 x 480 @ 75Hz, 37.5kHz Yes Yes
6 640 x 480 @ 85Hz, 43.27kHz Yes Yes
7 720 x 400 @ 70Hz, 31.5kHz Yes Yes
8 800 x 600 @ 56Hz, 35.1kHz Yes Yes
9 800 x 600 @ 60Hz, 37.9kHz Yes Yes
10 800 x 600 @ 72Hz, 48.1kHz Yes Yes
11 800 x 600 @ 75Hz, 46.9kHz Yes Yes
12 800 x 600 @ 85Hz, 53.7kHz Yes Yes
13 832 x 624 @ 75Hz, 49.7kHz Yes Yes
14 1024 x 768 @ 60Hz, 48.4kHz Yes Yes
15 1024 x 768 @ 70Hz, 56.5kHz Yes Yes
16 1024 x 768 @ 72Hz, 58.1kHz Yes Yes
17 1024 x 768 @ 75Hz, 60.0kHz Yes Yes
18 1024 x 768 @ 85Hz, 68.67kHz Yes Yes
19 1152 x 870 @ 75Hz, 68.6kHz Yes Yes
20 1280 x 1024 @ 60Hz, 63.4kHz Yes Yes
21 1280 x 1024 @ 75Hz, 79.97kHz Yes Yes
22 1280 x 720 @ 60Hz, 45kHz Yes Yes
Primary Preset:¡G VESA : 1280 x1024@60Hz
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2.3 INTERFACE DESCRIPTION
D-SUB 15 PIN CONNECTOR
Pin Number Pin Function
1 5
6 10 1 Red video input
11 15
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)
Horizontal sync (Composite
13
sync)
14 Vertical sync
15 (SCL)
SIGNAL LEVEL
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DVI-D 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 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 command line at the bottom of the control screen
tells what to do next from this screen. You can toggle
between control screens, adjust the selected option, or
exit the screen.
4. To adjust the setting, 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 1280 x 1024 @ 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 and down buttons.
Control Explanation
Auto Image Adjust sizes and centers the screen image automatically.
Contrast adjusts the difference between the image background (black level)
and the foreground (white level).
Brightness adjusts background black level of the screen image.
Input Select allows the user to toggle between an analog and a digital signal.
Audio Adjust
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).
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.
5000K-Adds blue and green to the screen image for a darker color.
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, press and .
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.
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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 1280 x 1024 @ 60Hz (recommended) means that the resolution
is 1280 x 1024 and the refresh rate is 60 Hertz.
Manual Image Adjust Sub-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.
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:
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Language Select allows the user to choose the language used in the menus
and control screens.
Resolution Notice allows the user to enable or disable this notice.
If you enable the Resolution Notice shown above and your computer is set at a
resolution other than 1280 x 1024, the following screen appears.
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 "30 second" setting, if a control is not pushed within 30
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.
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SHORT CUTS FUNCTION FROM THE BUTTONS
[1] Main Menu
[2] Auto Image Adjust
To immediately activate Contrast menu. It should be
[] or []
change to Brightness OSD by push button [2]
Recall Contrast or Brightness while in the Contrast or
[] + [] Brightness adjustment, or recall both of Contrast and
Brightness when the OSD is not open.
Toggle 720x400 and 640x400 mode when input 720x400
[1] + [2]
or 640x400 mode
[1] + [] + [] White Balance (Not shown on user's guide)
· Power Lock: Press and hold "[2], & " for 10 seconds. If
the power button is pressed the message Power Button
Locked will display for 5 seconds. With or without this
[1] + [] setting, after a power failure, your LCD display's power
will automatically turn ON when power is restored.
· Power Unlock: Press and hold "[2], & " again for 10
seconds.
· OSD Lock: Press and hold "[1], & ()" for 10 seconds. If
any buttons are pressed the message OSD Locked will
[1] + [] display for 5 seconds.
· OSD Unlock: Press and hold "[1], & " again for 10
seconds.
[ ] Volume mute on/off
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.
The Power Board will provide AC to DC Inverter voltage to drive the backlight of panel and the
Main Board chips each voltage.
Monitor Block Diagram
CCFL Drive. Flat Panel and
CCFL backlight
RS232 Connector
Power Board Main Board For white balance
adjustment in factory
(Include: adapter, inverter) mode
Video signal, DDC
Key Board
AC-IN
100V-240V HOST Computer
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4.2 POWER BLOCK FUNCTION DESCRIPTION
Inverter Block Function
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Power Block Function
4.3 Function Test and Alignment Procedure
All Modes Reset
You should do "All Mode Reset" (Refer to Chapter III-3. Hot Keys for Function
Controls) first. This action will allow you to erase all end-user's settings and restore
the factory defaults.
Auto Image Adjust
Please select and enter "Auto Image Adjust" function on Main Menu to see if it is
workable. The "Auto Image Adjust" function is aimed to offer a better screen quality
by built-in ASIC. For optimum screen quality, the user has to adjust each function
manually.
Firmware
Test Pattern: Burn In Mode (Refer to Chapter III-3. Hot Keys for Function Controls)
- Make sure the F/W is the latest version.
DDC
Test Pattern: EDID program
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Make sure it can pass test program.
Fine Tune and Sharpness
Test Signal: 1280*1024@60Hz
Test Pattern: Line Moire Pattern
Check and see if the image has noise and focus performs well. Eliminate visual
line bar.
If not, readjust by the following steps:
(a)Select and enter "Fine Tune" function on "Manual Image Adjust" to adjust the
image to eliminate visual wavy noise.
(b)Then, select and enter "Sharpness" function to adjust the clarity and focus of
the screen image.
Boundary
Test Signal: 1280*1024@60Hz
Test Pattern: Horizontal & Vertical Line Thickness Pattern
Check and see if the image boundary is within the screen frame.
If not, readjust by the following steps:
(a)Select and enter "Manual Image Adjust" function on OSD Main Menu.
(b)Then, select and enter "Horizontal Size" or "Horizontal/Vertical Position" function
to adjust the video boundary to be full scanned and within screen frame.
White Balance
Test Signal: 640*480@60Hz
Test Pattern: White and Black Pattern
1.5.8 R, G, B, Colors Contrast
Test Signal: 1280*1024@60Hz
Test Pattern: R, G, B, Color Intensities Pattern and 16 Gray Scale Pattern
- Check and see if each color is normal and distinguishable.
- If not, please return the unit to repair area.
Screen Uniformity and Flicker
Test Signal: 1280*1024@60Hz
Test Pattern: Full White Pattern
- Check and see if it is in normal condition.
1.5.10 Dead Pixel and Line
Test Signal: 1280*1024@60Hz
Test Pattern: Dark and White Screen Pattern
- Check and see if there are dead pixels on LCD panel with shadow gauge and
filter film.
- The total numbers and distance of dead pixels should be compliant with the
spec.
Mura
Test Pattern: White, RGB, Black, & Grey
Test Tool: 10% ND Filter
- Check if the Mura can pass 10% ND Filter.
Audio
Test Signal: Voice signal (optional, depend on model)
Test Pattern: liberty
- Make sure there is audio output.
- Make sure that audio function (volume 80%) is working without noise and
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resonance.
- Make sure that the sound of right and left speakers are in balance.
Check for Secondary Display Modes
Test Signal:
Analog: 640*350@70Hz; 640*480@60/67/72/75/85Hz;
720*400@70Hz; 800*600@56/60/72/75/85Hz;
832*624@75Hz, 1024*768@60/70/72/75/85Hz;
1280*1024@60/75Hz
Digital: 640*350@70Hz; 640*480@60/72/75/85Hz;
720*400@70Hz; 800*600@56/60/72/75/85Hz;
1024*768@60/70/72/75/85Hz; 1152*870@75Hz,
1280*720@60Hz, 1280*1024@60Hz
- Normally when the primary mode 1280*1024@60Hz is well adjusted and
compliant with the specification, the secondary display modes will also be
compliant with the spec. But we still have to check with the general test pattern to
make sure every secondary is compliant with the specification.
-
All Modes Reset
After final QC step, we have to erase all saved changes again and restore the
factory defaults. You should do "All Mode Reset" again.
Power Off Monitor
Turn off the monitor by pressing "Power" button.
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4.4 INTRODUCTION OF IC
RTD2523B-LF(U401): integrate ADC, OSD, TMPS, RSDS TX, LVDS TX, convert
analog RGB into digital and room and shrink scaling output to LCD panel.
PIN Function:
Pin Symbol Description
127 XO Crystal OSC output
128 XI Reference clock input from external crystal or from
single-ended CMOS/TTL OSC 3.3V tolerance
50 DDCSCL1 ADC Open drain Internal 75K pull high
51 DDCSDA1 ADC Open drain Internal 75K pull high
121 DDCSCL2 DVI Open drain Internal 75K pull high
120 DDCSDA2 DVI Open drain Internal 75K pull high
123 RESET_OUT Reset out Open drain( internal 75KOhm high)
110/48 COUT Crystal out
124 33VRST_REF Reference 3.3V for Reset Out
109 33VPNLOUT Panel on/off switch out Max current driving 1A
58 BJT_B Embedded regulator P type BJT control pin out
5 TMDS_TST TMDS_TEST Pin;
Power-on-latch for host interface type.
7/13 TMDS_VDD TMDS power 3.3V
6 REXT Impedance Match Reference.
49/112 PWM2
4/48/111 PWM1
3/5/122 PWM0
4 BYPASS For External Bypass Capacitor
125 DPLL_VDD Power for digital PLL 3.3V
2 APLL_VDD Power for multi-phase PLL 3.3V
3 PLL_TEST1 Test Pin 1;Power-on-latch for MCU crystal location
4 PLL_TEST2 Test Pin 2;Power-on-latch for crystal in frequency
56/118 SCSB Serial control I/F chip select Open drain
57/119 SCLK Serial control I/F clock Open drain
59/83/108 Pad 3.3V Power PVCC
47/116 Digital 1.8V Power VCCK
21/38 ADC_VDD ADC Power 1.8V
40 VCLK Video8 Clock
19 AVSO ADC vertical sync input
5V tolerance
Power from PIN 13
20 AHSO ADC horizontal sync input
Adjustable Schmidt trigger 5V tolerance
Power from PIN 13
AIC1084-33PM (U701): DC power convert, used to 5v convert 3.3v.
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MTV512GMV64 (U402): The MTV512M micro-controller is an 8051 CPU core
embedded device especially tailored for flat panel display applications. It
includes an 8051 CPU core, 768-byte SRAM, 4 channels of 6-bit ADC, 3
external counters/timers, 6 channels of PWM DAC, VESA DDC interface,
and a 64K-byte internal program Flash-ROM memory.
Circuit Diagram
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PIN Function
Pin No.
Name DESCRIPTION
PLCC QFP
NC 1 39 No connection
DA0/P5.0 2 40 PWM DAC output/General purpose I/O (open drain)
DA1/P5.1 3 41 PWM DAC output/General purpose I/O (open drain)
DA2/P5.2 4 42 PWM DAC output/General purpose I/O (open drain)
DA3/P5.3 5 43 PWM DAC output/General purpose I/O (open drain)
DA4/P5.4 6 44 PWM DAC output/General purpose I/O (open drain)
DA5/P5.5 7 1 PWM DAC output/General purpose I/O (open drain)
P5.6/HSCL2 8 2 General purpose I/O/Slave llC1 SCL2 open drain
P5.7/HSDA2 9 3 General purpose Output/Slave llC1 SCL2 open drain
RST 10 4 High Active RESET
HSCL1/P3.0/RXD 11 5 Slave IIC clock/General purpose I/O/Rxd (open drain)
HSDA1/P3.1/RXD 13 7 Slave IIC clock/General purpose I/O/Txd (open drain)
P3.2/INT0 14 8 General purpose I/O/External interrupt 0(Standard 8051)
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P3.3/INT1 15 9 General purpose I/O/External interrupt 1(Standard 8051)
P3.4/T0 16 10 General purpose I/O/T0 Ext. Counter/Timer 0(Standard8051)
P3.5/T1 17 11 General purpose I/O/T1 Ext. Counter/Timer 1(Standard8051)
P7.6/CLKO2 18 12 General purpose I/O/Clock out 2 (CMOS)
P7.7 19 13 General purpose I/O (CMOS)
X2 20 14 Crystal Out
X1 21 15 Crystal In
VSS 22 16 Ground
P6.0/AD0 24 18 General purpose I/O(COMS)/6-bit ADC channel 0 input
P6.1/AD1 25 19 General purpose I/O(COMS)/6-bit ADC channel 1 input
P6.2/AD2 26 20 General purpose I/O(COMS)/6-bit ADC channel 2 input
P6.3/AD3 27 21 General purpose I/O(COMS)/6-bit ADC channel 3 input
P6.4 28 22 General purpose I/O(COMS)
P6.5 29 23 General purpose I/O(COMS)
P6.6/CLKO1 30 24 General purpose I/OCLKO1(COMS)
P6.7 31 25 General purpose I/O(COMS)
VSYNC 32 26 VSYNC input
P1.7 36 30 General purpose I/O(Standard 8051/CMOS)
P1.6 37 31 General purpose I/O(Standard 8051/CMOS)
P1.5 38 32 General purpose I/O(Standard 8051/CMOS)
P1.4 39 33 General purpose I/O(Standard 8051/CMOS)
P1.3 40 34 General purpose I/O(Standard 8051/CMOS)
P1.2 41 35 General purpose I/O(Standard 8051/CMOS)
P1.1 42 36 General purpose I/O(Standard 8051/CMOS)
43 General purpose I/O/External Counter/Timer2(Standard
P1.0/ET2 37 8051/CMOS)
VCC 44 38 3.3V power
TDA7496L (U201): The UTC TDA7496L is a stereo 2W+2W class AB power amplifier,
specially designed for high quality sound, TV and Monitor applications.
Features of the UTC TDA7496L include linear volume control, Stand-by and
mute functions.
Pin Function
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Circuit Diagram
LD7552BS (IC901): PWM control, high-voltage startup current. The circuit unit has
functions such as over-current protection, over-voltage protection, output short-circuit
protection and etc. The function of each pin and the inside circuit diagram are as
follows:
Pin Name Function
1 GND Ground
Voltage feedback pin (same as the COMP pin in UC384X), By
2 COMP connecting a photo-coupler to close the control loop and achieve the
regulation
3 VCC Supply voltage pin
This pin is to program the switching frequency. By connecting a resistor
4 RT
to ground to set the switching frequency.
6 NC Unconnected pin
7 VCC Supply voltage pin
8 OUT Gate drive output to drive the external MOSFET
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FAN7547A(IC201): The FAN7547A provides all control functions for a current fed
push-pull self oscillation type converter, and also contains voltage. Typical
operating frequency range is between 30kHz depending on the CCFL(Cold
Cathode Fluorescent Lamp) and the transformer's characteristics:
NO. Name Function Description NO. Name Function Description
1 GNDT Ground 8 FB Feedback Input
2 Vds Dimming Voltage Input 9 COMP Error Amplifier Output
3 Vref Reference Voltage 10 S/S Soft Start
4 Vms Dimming Mode Selection 11 OSC Main Ct
Burst Dimming Frequency
5 Rct 12 Vcc Supply Voltage
Set
6 OLP Open Lamp Protection 13 Vcc1 Output Drive Source Voltage
7 SDP Shutdown Protection 14 OUT Output Drive
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5. Adjustment Procedure
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. White Balance Function Key
2. Geometry Function Key
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¡BReference to Chroma 7120 user guide
B¡BUse " 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¡BMEM.CHANNEL9 ( 9300 color):
9300 color temp. parameter is Wx = 0.283 ¡Ó0.02;Wy = 0.298 ¡Ó 0.02;
2,
Y > 190 cd/m
B¡BMEM.CHANNEL10 ( 6500 color):
6500 color temp. parameter is Wx = 0.313¡Ó0.02;Wy = 0.329 ¡Ó0.02;
2,
Y > 260 cd/m
C¡BMEM.CHANNEL 11 ( 5400 color):
5400 color temp. parameter is Wx = 0.335¡Ó0.02;Wy = 0.350 ¡Ó0.02;
2,
Y > 210 cd/m
D¡BMEM.CHANNEL 12 ( 5000 color):
5000 color temp. parameter is Wx = 0.346¡Ó0.02;Wy = 0.359 ¡Ó0.02;
2
Y > 210 cd/m
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E¡B MEM.CHANNEL13 ( SRGB color):
SRGB color temp. parameter is Wx = 0.313¡Ó 0.02;Wy = 0.329 ¡Ó 0.02;
Y > 220 cd/m2,
3.)Into factory mode of VA712b-2
A¡B First Power off, then press Switch 2 button along with press Power button will activate the
factory mode, then MCU will do AUTO LEVEL automatically. Meanwhile press MENU the OSD
screen will located at LEFT TOP OF PANEL.
4.)Bias adjustment :
Set the Contrast to 70
Adjust the Brightness to 100.
5.)Gain adjustment :
Move cursor to "-F-" and press MENU key
A¡B Adjust 9300 color-temperature
(1)¡B Switch the Chroma-7120 to RGB-Mode (with press "MODE" button )
(2)¡B Switch the MEM. channel to Channel 9 ( with up or down arrow on Chroma 7120 )
(3)¡B The LCD-indicator on Chroma 7120 will show x = 0.283 ¡Ó 0.02, y =0.298 ¡Ó 0.02, Y>
2
250 cd/m
(4)¡B Adjust the RED of color1 on factory window until chroma 7120 indicator reached the
value R=100
(5)¡B Adjust the GREEN of color1 on factory window until Chroma 7120 indicator reached the
value G=100
(6)¡B Adjust the BLUE of color1 on factory window until Chroma 7120 indicator reached the
value B=100
(7)¡B Repeat above procedure ( item 4,5,6) until Chroma 7120 RGB value meet the
tolerance =100¡Ó 5
B¡B Adjust 6500 color-temperature
(1)¡B Switch the chroma-7120 to RGB-Mode (with press "MODE" button )
(2)¡B Switch the MEM .channel to Channel 10( with up or down arrow on Chroma 7120 )
(3)¡B The LCD-indicator on Chroma 7120 will show x = 0.313 ¡Ó 0.02, y = 0.329 ¡Ó 0.02, Y>260
cd/m2
(4)¡B Adjust the RED of color3 on factory window until Chroma 7120 indicator reached the
value R=100
(5)¡B Adjust the GREEN of color3 on factory window until Chroma 7120 indicator reached the
value G=100
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(6)¡B Adjust the BLUE of color3 on factory window until Chroma 7120 indicator reached the
value B=100
(7)¡B Repeat above procedure ( item 4,5,6) until Chroma 7120 RGB value meet the
tolerance =100¡Ó 5
C¡B Adjust 5400 color-temperature
(1) Switch the chroma-7120 to RGB-Mode (with press "MODE" button )
(2)¡B Switch the MEM .channel to Channel 11( with up or down arrow on Chroma 7120 )
(3)¡B The LCD-indicator on Chroma 7120 will show x = 0.335 ¡Ó 0.02, y = 0.350 ¡Ó 0.02, Y>210
cd/m2
(4)¡B Adjust the RED of color3 on factory window until chroma 7120 indicator reached the value
R=100
(5)¡B Adjust the GREEN of color3 on factory window until Chroma 7120 indicator reached the
value G=100
(6)¡B Adjust the BLUE of color3 on factory window until Chroma 7120 indicator reached the
value B=100
(7)¡B Repeat above procedure ( item 4,5,6) until Chroma 7120 RGB value meet the
tolerance =100¡Ó 5
D¡B Adjust 5000 color-temperature
(1) Switch the chroma-7120 to RGB-Mode (with press "MODE" button )
(2)¡B Switch the MEM .channel to Channel 11( with up or down arrow on Chroma 7120 )
(3)¡B The LCD-indicator on Chroma 7120 will show x = 0.346 ¡Ó 0.02, y = 0.359 ¡Ó 0.02, Y>210
cd/m2
(4)¡B Adjust the RED of color3 on factory window until chroma 7120 indicator reached the value
R=100
(5)¡B Adjust the GREEN of color3 on factory window until Chroma 7120 indicator reached the
value G=100
(6)¡B Adjust the BLUE of color3 on factory window until Chroma 7120 indicator reached the
value B=100
(7)¡B Repeat above procedure ( item 4,5,6) until Chroma 7120 RGB value meet the
tolerance =100¡Ó 5
E¡B Adjust SRGB color-temperature
(1)¡B Switch the chroma-7120 to RGB-Mode (with press "MODE" button )
(2)¡B Switch the MEM .channel to Channel 10( with up or down arrow on chroma 7120 )
(3)¡B The LCD-indicator on chroma 7120 will show x = 0.313 ¡Ó 0.02, y = 0.329 ¡Ó 0.02, Y>220
cd/m2
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(4)¡B Adjust the RED of color3 on factory window until Chroma 7120 indicator reached the
value R=100
(5)¡B Adjust the GREEN of color3 on factory window until Chroma 7120 indicator reached the
value G=100
(6)¡B Adjust the BLUE of color3 on factory window until Chroma 7120 indicator reached the
value B=100
(7)¡B Repeat above procedure ( item 4,5,6) until Chroma 7120 RGB value meet the tolerance
=100¡Ó 5
E¡¢ Press reset key and Turn the Power-button "off to on" to quit from factory mode.
2. Geometry
1).Set cross-hatch pattern and preset timing as timing table listed.
2).Change to each mode in turn and wait for the monitor finish auto-alignment and save
press before change to next mode.
3).Until all of modes are adjusted, exit OSD menu and press POWER OFF to exit factory
mode.
5.4 Factory Defaults
Item Defaults Item Defaults
Contrast 70% OSD H. Position 50%
Brightness 100% OSD V. Position 50%
Volume 50% OSD Time Out 15 Sec
Color Temperature 6500K Resolution Notice Enable
Sharpness 33% OSD background Enable
720X400/640X400 720X400
5.5 Function Test
1 Product: 17" LCD Monitor
2 Test Equipment: Color Video Signal & Pattern (or PC with SXGA resolution and a
sound card)
3 Test Condition: Before function test and alignment, each LCD Monitor should be
warmed up for at least 30 minutes with the following conditions:
(a)In room temperature,
(b) With full-white screen, RGB, and Black
(c) With cycled display modes,
640*480 (H=43.27kHz, V=85Hz)
800*600 (H=53.7kHz, V=85Hz)
1024*768 (H=68.67kHz, V=85Hz)
1280*1024 (H=79.97kHz, V=75Hz)
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4 Test Display Modes & Pattern
Compatible Modes
Analog Digital
640 x 350 @ 70Hz, 31.5kHz 640 x 350 @ 70Hz, 31.5kHz
640 x 400 @ 70Hz, 31.5kHz 640 x 400 @ 70Hz, 31.5kHz
640 x 480 @ 60Hz, 31.5kHz 640 x 480 @ 60Hz, 31.5kHz
640 x 480 @ 67Hz, 35.0kHz 640 x 480 @ 67Hz, 35.0kHz
640 x 480 @ 72Hz, 37.9kHz 640 x 480 @ 72Hz, 37.9kHz
640 x 480 @ 75Hz, 37.5kHz 640 x 480 @ 75Hz, 37.5kHz
720 x 400 @ 70Hz, 31.5kHz 720 x 400 @ 70Hz, 31.5kHz
800 x 600 @ 56Hz, 35.1kHz 800 x 600 @ 56Hz, 35.1kHz
800 x 600 @ 60Hz, 37.9kHz 800 x 600 @ 60Hz, 37.9kHz
800 x 600 @ 75Hz, 46.9kHz 800 x 600 @ 75Hz, 46.9kHz
800 x 600 @ 72Hz, 48.1kHz 800 x 600 @ 72Hz, 48.1kHz
832 x 624 @ 75Hz, 49.7kHz 832 x 624 @ 75Hz, 49.7kHz
1024 x 768 @ 60Hz, 48.4kHz 1024 x 768 @ 60Hz, 48.4kHz
1024 x 768 @ 70Hz, 56.5kHz 1024 x 768 @ 70Hz, 56.5kHz
1024 x 768 @ 72Hz, 58.1kHz 1024 x 768 @ 72Hz, 58.1kHz
1024 x 768 @ 75Hz, 60.0kHz 1024 x 768 @ 75Hz, 60.0kHz
1280 x 1024 @ 60Hz, 63.4kHz 1280 x 1024 @ 60Hz, 63.4kHz
1280 x 1024 @ 75Hz, 79.97kHz 1280 x 1024 @ 75Hz, 79.97kHz
1280x 720 @ 60Hz, 45kHz 1280x 720 @ 60Hz, 45kHz
Function Test Display Pattern
Item Test Content Pattern Specification Remark
Frequency & Eliminate visual wavy
1 Fine Line Moire Figure 1
Tracking noise.
Contrast/Bright 16 gray levels sh should
2 16 Gray Scale Figure 2
ness be distinguishable.
Horizontal and Vertical
Horizontal&Vertical position of video should
3 Boundary Figure 3
Thickness be adjustable to be
within the screen frame.
Contrast of each R, G,
RGB Color Figure
4 RGB Color Intensities B, color should be
Performance 4,5,6
normal.
Screen
Should be compliant
5 Uniformity & Full White Figure 7
with the spec.
Flicker
The numbers of dead
Dead White Screen & Dark
6 pixels should be Figure 7,8
Pixel/Line Screen
compliant with the spec.
The screen must have
7 White Balance White & Black Pattern the pure white and black Figure 9
pattern, no other color.
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Fine Line Morie Pattern (Figure1) Gray Scale Pattern (Figure2)
Horizontal & Vertical Thickness Pattern R. Color Pattern (Figure 4)
(Figure 3)
G. Color Pattern (Figure 5) B. Color Pattern (Figure 6)
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Full White Pattern (Figure 7) Dark Screen Pattern (Figure 8)
Black-White Pattern (Figure 9)
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5.6 Firmware Upgrade Procedure
When you receive the returned monitor, please check whether the firmware version is
the latest. If not, please do the following procedures to upgrade it to the latest version.
1 Equipment Needed
- VA712-2/VA712b-2 Monitor
- Fixture for Firmware Upgrade
- Power Adapter (P/N: 47.58201.001) *1 for Fixture
- VGA Cable (P/N: 42.59901.003) *1(Pin 4, 11 should be connected to GND)
- PC (Personal Computer)
- LPT Cable (P/N: 42.59906.001) *1
- Firmware Upgrade Program
- One additional monitor for checking the program execution
2 Setup Procedure
2.1 Connect P1 of Fixture with printer port of PC by LPT Cable.
2.2 Connect P2 of Fixture with VA712-2/VA712b-2 Monitor by VGA Cable.
2.3 Connect Power Cord to VA712-2/VA712b-2 Monitor.
2.4 Connect P3 to the Signal Generator (eg.Chroma2326) for verifying it after the
operation being completed.
2.5 Connect PC to the additional monitor.
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3 Firmware Upgrade Procedure
Step 1. Let VA712-2/VA712b-2 set to be connected with AC cable and VGA cable.
Step 2.Execute the MSstar ISP tool.
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Step 3. Click "Create Security File" button. Open a new window to key in security code.
Step 4.Set "Command NO" to 4,and key in security code :"94,94,ac,ca,53" to shown as
following, then press "OK" button to close window.
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Step 5. Click dropdown listbox for MTV type, select the "MTV512M64" viewed on your
set.
Step 6. Click "Load MCU File" button. Select the object bincode on your corresponding
directory.
Step 7. Click " " button to finish the selection of bincode.
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Step 8. Select "Auto" optionbutton, then execute the flashing action by clicking the
"RUN" button.
Step 9. If the flashing F/W has been completed, the message of "Check MCU CRC OK"
on the right TextBox means the Host verify ok for the progress of program.
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Step 10. Unplug and replug power cord of VA712-2/VA712b-2 set and then check the
OSD operation and image on srceen.
Step 11. At last, do "Memory Recall."
3.2 Setup Procedure
3.2.1 Connect P2 and monitor of Fixture with VGA ports of VA712-2/VA712b-2 by VGA
Cable.
3.2.2 Connect P3 of Fixture with DVI port of VA712b-2 by DVI-DVI Cable.
3.2.3 Connect P1 of Fixture with Printer port of PC by LPT Cable.
3.2.4 Plug Power Adapter to Fixture.
3.2.5 Connect Power Cord to VA712-2/VA712b-2 Monitor.
3.2.6 Connect PC to the additional monitor.
JP1 Power Adapter
P3 DVI-DVI Cable
P2 VGA Cable
P1 to LTP Cable
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3.3 DDC Key In Procedure
Sep1.Select and execute DDC Key In program
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Sep2:Inpute the S/N and execute "Enter"
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Sep3:Key the "Enter" and write the data
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Sep4:If ddc program OK and show "data compare ok"
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Disassemble Process
1.1. Units Disassemble Process
1.1.1. Tools
Glove
Big cross screwdriver
Small cross screwdriver
Prize equipment or abandoned IC card
Screw box
Cushion
Six angle sleeve spanner
1.1.2. Disassemble process
1 Tide up the worktable, spread straight cushion, put the monitor on it, the front side
adown.(Picture 1, 2)
2 Disassemble the 4 screws that fix the stand, remove the stand..(Picture 3, 4)
3 Disassemble the fix screws of the back cover. Picture 5
4 Use equipment or abandoned IC card to prize up the bezel through the bottom flute,
as showed in the following the picture 6,7, and rip up the back cover downwards.( as
showed in the following the picture 8,9,10)
5 Disassemble the 4 screw M3*6MM through six angle sleeve spanner, showed in the
following picture 11.
6 Disassemble the 4 fixed screws in the shield, remove the shield as the direction
arrowhead showed, refer to the following picture 12.
7 Disassemble the 4 screws and 4 pins of the PWPC board, remove the PWPC
board.(symbolized the following picture 13 with red color)
8 Disassemble the 3 screws and 4 pins of the main board, remove the main board.
(symbolized the following picture 13 with blue color)
9 Disassemble the 2 screws of the audio board, remove the audio board. (symbolized
the following picture 13 with green color)
10 Disassemble the 3 screws and connect pins of the Key board, remove the Key board,
refer to the following picture 14,15 .
11 Disassemble the 2 fixed screws of the main frame, and remove the bezel, as showed
in the following the picture 16,17.
12 Disassemble the 2 fixed screws of the panel, remove the main frame, as showed in
the following the picture 18,19,20. Do not damage the cable of the panel.
13 That's all. The disassemble process of the unit is over.
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1.1.3 Show pictures¡G
Picture 1 Picture 2
Picture 3 Picture 4
Picture 5 Picture 6
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Picture 7 Picture 8
Picture 9 Picture 10
Picture 11 Picture 12
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Picture 13
Picture 14
Picture 15
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Picture 16
Picture 17
Picture 18
Picture 19
Picture 20
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6. Troubleshooting Flow Chart
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7. Recommended Spare Parts List
RECOMMENDED SPARE PARTS LIST (VA712-2)
ViewSonic Model Number: VS10901-1W
Rev: 1a
Serial No. Prefix: PX5
Item Description ECR/ECN ViewSonic P/N Ref. P/N Location Universal number# Q'ty
1 Accessories: POWER CORD A-00004962 89G404A18N LS 1PCS
2 Board Assembly: AUDIO BOARD B-00004963 AUPC780B3P 1PCS
3 CONVERSION BOARD B-00005609 CBPC780KCWV4P 1PCS
4 KEY BOARD B-00005610 KEPC780KE1P 1PCS
5 POWER BOARD B-00005611 PWPC1742CPV2P 1PCS
6 Cabinets: FRONT PANEL (BEZEL) C-00005612 34G1750AKD B 1PCS
7 REAR COVER C-00005613 34G1751 KR 2B 1PCS
8 BASE ASSY C-00005649 34G1754 KR B 1PCS
9 Cables: SIGNAL CABLE CB-00003768 89G 728HAA902 1PCS
10 AUDIO CABLE CB-00004972 89G 173 56 31 1PCS
11 WIRE (AUDIO BOARD HARNESS) CB-00005614 95G8014 14 34 1PCS
12 KEY BOARD HARNESS CB-00005615 95G8014 16926 1PCS
13 WIRE HARNESS CB-00005616 95G8018 30910 1PCS
14 Documentation CARTON LABEL DC-00003727 40G 459709 1B 1PCS
15 H/V WARNING LABEL DC-00003729 40G 459709 4A 1PCS
16 Hg LABEL DC-00003730 40G457B709 1A 1PCS
17 HI-POT LABEL FOR 17-L DC-00003731 40G 459709 5A 1PCS
18 QSG DC-00005617 41G7801709 6A 1PCS
19 CD MANUAL DC-00005618 70G1701709 8A 1PCS
20 S/N LABEL DC-00005635 40G581B709 4A 1PCS
21 MANUAL P/N LABEL DC-00005636 40G 58162435A 1PCS
22 ID LABEL DC-00005637 J40G170T709 1A 1PCS
23 BLUE STICKER-2 DC-00005638 40G581B709 2B 1PCS
24 8ms STICKER DC-00005639 40G581B709 3A 1PCS
25 Electronics: IC M24C02-WMN6TP E-00003738 56G1133 34 U405 1PCS
26 IC M24C16-WMN6TP E-00004982 56G1133 56 U404 1PCS
27 LCD PANEL E-00005619 750GLC70A7Q 12 1PCS
28 SPEAKER E-00005620 78G 311 8 L 1PCS
29 SPEAKER E-00005621 78G 311 8 R 1PCS
30 IC AMPLIFIER E-TDA749 E-00005622 56G 616 1 U201 1PCS
31 RTD2023L-LF LQFP-48 E-00005650 56G 562115 U403 1PCS
32 AIC1084-33PM TO-263 E-00005651 56G 563 7 U701 1PCS
33 MTV512MV PLCC-44 MYSO E-00005652 56G1125543CA4 U402 1PCS
34 Hardware: MAIN FRAME HW-00005623 15G8267 1 1PCS
35 HINGE HW-00005624 37G 552 1 1PCS
36 SCREW HW-00005625 M1G 130 6120 4PCS
37 SCREW HW-00005626 M1G 330 4128 4PCS
38 SCREW HW-00005627 M1G1140 6128 1PCS
39 SCREW HW-00005628 M1G1730 6128 3PCS
40 SCREW HW-00005629 M1G1740 12120 4PCS
41 SCREW HW-00005630 Q1G 130 6120 2PCS
42 SCREW HW-00005631