ViewSonic VG920-1 Service manual

Service Manual

ViewSonic VG920-1

Model No. VS10790

19” Color TFT LCD Display

ViewSonic

(VG920-1_SM Rev. 1b Aug. 2006)



381 Brea Canyon Road, Walnut, California 91789 USA - (800) 888-8583

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.

Disclai mer

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

1a 12/08/2005 Initial release Jamie Chang

1b 08/08/2006

SM Editing Date ECR Number Description of Changes

HSD190ME13-A16 panel source Jamie Chang

VS-E060218

Add

Editor

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TABLE OF CONTENTS

1. Precautions and Safety Notices

2. Specification

3. Front Panel Function Control Description

4. Circuit Description

5. Adjusting Procedure

6. Trouble Shooting Flow Chart

7. Recommended Spare Parts List

8. Exploded View And Exploded Parts List

9. Block Diagram

10. Schematic Diagrams

11. PCB Layout Diagrams

50 64

67 68

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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

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

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.

．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

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 pad.

Placing the monitor on foreign objects. That could scratch the surface of the panel or cause “Mura.”

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

The panel is placed facedown on the lap. That may cause “Mura.”

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2. Specification

2.1 PRODUCT SPECIFICATIONS

Panel Characteristics :

Source Panel e

AUO M190EN04 V51 Type TN Technology” Active Size 376.32 (H) x 301.06 (V) Pixel Arrangement RGB Vertical Stripe Pixel Pitch 0.294 mm GLASS TREATMENT Anti Glare (Hard coating 3H) # OF BACKLIGHTS 4 CCFL edge-light (2 top / 2 bottom) BACKLIGHT LIFE 50,000 Hours (Typ) / 40,000 Hours (Min) Luminance –

Condition:

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

215 cd/m2 (Min after 30 minute warm up) CT = 6500K, Contrast = Max, Brightness = Max Brightness Uniformity 75 % Entire Area (Typ), 70% (min) Contrast Ratio 550:1 (Typ), 350:1 (Min) Color Depth 16 million colors (6 bit panel + 2 bit FRC) Viewing Angle (Horizontal) 140 deg @ CR>10, ??? deg @ CR>5 VIEWING ANGLE (VERTICAL) 135 deg @ CR>10, ??? deg @ CR>5 Response Time 10%-90% @ Ta=25°C

8 ms (Tr= 5.6 ms, Tf = 2.4 ms) (Typ)

12 ms (Tr= 8.4 ms, Tf = 3.6 ms) (Max) Panel Defects Please see Panel Quality Specifications.

Source Panel

BOE HT190E01-100

Type “TN Technology” Active Size 376.32 (H) x 301.06(V) Pixel Arrangement RGB Vertical Stripe Pixel Pitch 0.294 mm GLASS TREATMENT Anti Glare (Hard coating 3H) # OF BACKLIGHTS 4 CCFL edge-light (2 top / 2 bottom) BACKLIGHT LIFE 50,000 Hours (Min) Luminance – Condition:

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

250 cd/m2 (Min after 30 minute warm up) CT = 6500K, Contrast = Max, Brightness = Max Brightness Uniformity 75 % Entire Area (minimum) Contrast Ratio 700:1 (Typ), 550:1 (Min) Color Depth 16 million colors (6 bit panel) Viewing Angle (Horizontal) 150 deg @ CR>10, 160 deg @ CR>5 VIEWING ANGLE (VERTICAL) 135 deg @ CR>10, 160 deg @ CR>5 Response Time 10%-90% @ Ta=25°C

8 ms (Tr= xx ms, Tf = xx ms) (Typ)

12 ms (Tr= xx ms, Tf = xx ms) (Max) Panel Defects Please see Panel Quality Specifications.

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Source Panel

Hannstar HSD190ME13-A16

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

240 cd/m2 (Min after 30 minute warm up)

CT = 6500K, Contrast = Max, Brightness = Max Brightness Uniformity 70 % (minimum) Contrast Ratio 700:1 (Typ), 460:1 (Min) Color Depth 16.2 million colors (6 bit panel) Viewing Angle (Horizontal) 150 deg @ CR>10,160 deg @ CR>5 VIEWING ANGLE (VERTICAL) 135 deg @ CR>10, 155 deg @ CR>5 Response Time 10%-90% @ Ta=25°C

8 ms (Tr= xx ms, Tf = xx ms) (Typ)

12 ms (Tr= xx ms, Tf = xx ms) (Max)

Panel Defects Please see Panel Quality Specifications.

2.2 INTERFACE DESCRIPTION

D-SUB 15 PIN CONNECTOR

11 15

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 N o co n nec tio n

12 (SDA)

13 Horizontal sync (Composite sync)

14 Vertical sync

15 (SCL)

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SIGNAL LEVEL

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 Controls And Indicators

Mute： Audio Mute button turns the sound off

Power LED (Front Head)

Volume+/ Volume-：Decreases or increases volume

Button 1：Scrolls through menu options and adjusts the displayed

control. Also a shortcut to display the Contrast adjustment control screen.

[▲]、[▼]：Displays the control screen for the highlighted control. Also

toggles between two controls on some screens. Also a shortcut to toggle analog and digital connection.

Button 2：Displays the control screen for the highlighted control. Also toggles

between two controls on some screens. Also a shortcut to toggle analog and

digital connection.

Power：Standby Power On/Off

Green – ON Orange – Active Off Dark = Soft Power Switch OFF

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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

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.

and down buttons.

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. 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.

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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 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]

[▼] or [▲]

[▼] + [▲]

[;+] or [;-]

[;+] + [;X]

[1] + [2]

[1] + [;X]

[2] + [▼]

[1] + [▲]

Input toggle (Analog or Digital).

To immediately activate Contrast menu. It should be change to Brightness OSD by push button [2]

recall both of Contrast and Brightness to default

To immediately activate Volume menu for audio volume.

Recall volume to default

toggle 720x400 and 640x400 mode when input 720x400 or 640x400 mode

White Balance. (Not shown on user’s guide)

• Power Button 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 setting, after a power failure, your LCD display’s power will automatically turn ON when power is restored.

• Power Button 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

display for 5 seconds.

• OSD Unlock: Press and hold “[1], & ▲” again for 10 seconds.

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.

Flat Panel and CCFL backlight

Main Board

HOST Computer

Power Board

(Include: adapter, inverter)

AC-IN

100V-240V

Monitor Block Diagram

CCFL Drive.

Key Board

RS232 Connector For white balance adjustment in factory mode

Video signal, DDC

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

EPROM EPROM

PWPC board

TSUM56AK

OSC

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

Start Circuit R903, R904,R905

Lamp

OSC and Output Circuit

Feedback Circuit

PWM

Control IC

Over Voltage

DC Convert Circuit

MOSFET Q203

PWM Control IC

Over Vol tage Protect

12V

ON/OF

ON/OFF Control

DIM

CN902

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4.4 INTRODUCTION OF IC

STUM56AK(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

36 DDCD_SDA DDC data for DVI interface; 4mA driving strength;

I/O w/5V-tolerant 37 DDCD_SCL DDC clock for DVI interface; Input w/5V-tolerant 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＿DVI

21 PWM1 PWM1; 4mA driving strength; Output 29 PWM0 PWM0; 4mA driving strength; Output

4 BYPASS For External Bypass Capacitor 33 XIN Xin; Crystal Oscillator Input 34 XOUT Xout; Crystal Oscillator Output

44、50 AVDD＿DVI

60 52 34

14、67、95、

103、115

13、38、41、

AVDD＿ADC

AVDD＿PLL

AVDD＿MPLL

VDDP Digital Output Power 3.3V

VDDC Digital Core Power 1.8V

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

47、96、116

AIC1084-33PM (U702): DC power convert, used to 5v convert 3.3v.

LT1117-18(U701): DC power convert, used to 5v convert 3.3v.

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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:

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 ground 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 V2P5 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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NCP1203D60R2G (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 No.

Pin Name

1 Adj

2 FB

3 CS Current sense input

Function Pin Description

Adjust the skipping

peak current

Sets the peak

current setpoint

This pin lets you adjust the level at which the cycle skipping process takes place. Shorting this pin to ground, permanently disables the skip cycle feature.

By connecting an optocoupler to this pin, the peak current setpoint is adjusted accordingly to the output power demand. Skip cycle occurs when FB falls below Vpin1.

This pin senses the primary current and routes it to the

internal comparator via an L.E.B. 4 GND The IC ground − 5 Drv Driving pulses The driver’s output to an external MOSFET.

6 VCC Supplies the IC

7 NC −

Ensure a clean and

8 HV

lossless startup

sequence

This pin is connected to an external bulk capacitor of

typically 22 F.

This unconnected pin ensures adequate creepage

distance.

Connected to the high−voltage rail, this pin injects a

constant current into the VCC capacitor during the startup

sequence.

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TL1451 (IC201): 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 and the circuit diagram inside are as follows:

Pin Symbol Description Pin Symbol Description

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

7 1OUT Output 1 15 SCP Timing latch setting

8 GND Ground 16 REF Reference voltage output (2.5v)

Output 1 dead time/soft start setting

14 2IN- Positive input for error amplifier

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4.5 POWER BLOCK FUNCTION DESCRIPTION

Inverter Block Function

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Power Block Function

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5. Adjusting 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、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;

Y = 250 ±20 cd/m

B、MEM.CHANNEL10 ( 6500 color):

6500 color temp. parameter is Wx = 0.313±0.03;Wy = 0.329 ±0.03; Y = 260 ±20 cd/m

C、MEM.CHANNEL 11 ( 5400 color):

5400 color temp. parameter is Wx = 0.335±0.03;Wy = 0.350 ±0.03; Y = 250 ±20 cd/m

D、MEM.CHANNEL10 ( SRGB color):

6500 color temp. parameter is Wx = 0.313±0.03;Wy = 0.329 ±0.03; Y = 220 ±20 cd/m

2 ,

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3.)Into factory mode of VG720

A、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

Adjust the Brightness

to 70

to 100.

5.)Gain adjustment : Move cursor to “-F-” and press MENU key

A、Adjust 9300 color-temperature

(1)、Switch the Chroma-7120 to RGB-Mode (with press “MODE” button ) (2)、Switch the MEM. channel to Channel 9 ( with up or down arrow on chroma 7120 ) (3)、The LCD-indicator on chroma 7120 will show x = 0.283 ±0.03, y =0.298 ±0.03,

Y = 250 ±20 cd/m

(4)、Adjust the RED of color1 on factory window until chroma 7120 indicator reached

the value R=100

(5)、Adjust the GREEN of color1 on factory window until chroma 7120 indicator reached

the value G=100

(6)、Adjust the BLUE of color1 on factory window until chroma 7120 indicator reached

the value B=100

(7)、Repeat above procedure ( item 4,5,6) until chroma 7120 RGB value meet the

tolerance =100±5

B、Adjust 6500 color-temperature

(1)、Switch the chroma-7120 to RGB-Mode (with press “MODE” button ) (2)、Switch the MEM .channel to Channel 10( with up or down arrow on chroma 7120 ) (3)、The LCD-indicator on chroma 7120 will show x = 0.313 ±0.03, y = 0.329 ±0.03, Y =

260 ±20 cd/m

(4)、Adjust the RED of color3 on factory window until chroma 7120 indicator reached

the value R=100

(5)、Adjust the GREEN of color3 on factory window until chroma 7120 indicator reached

the value G=100

(6)、Adjust the BLUE of color3 on factory window until chroma 7120 indicator reached

the value B=100

(7)、Repeat above procedure ( item 4,5,6) until chroma 7120 RGB value meet the

tolerance =100±5

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