AOC 712Sa Service Manual

17” LCD Color Monitor AOC 712Sa

HZ Service

Service

Horizontal Frequency

30kHz – 80kHz

TABLE OF CONTENTS

Description Page Description Page

Table Of Contents.......……..……..........................…........1

Revision List.….............……..........................……......2

Important Safety Notice.…………....................……......3

1. Monitor Specification..............................………........4

2. LCD Monitor Description…………………………….......5

3. Operation Instruction…………...............……...........6

3.1 General Instructions...........................…...........6

3.2 Control Button…………….…..............……...............6

3.3 Adjusting the Picture...........................…............8

4. Input/Output Specification............……………............10

N

4.1 Input Signal Connector............………….................10

4.2 Factory Preset Display Modes.........................10

4.3 Panel Specification.....………………..................11

5. Block Diagram……...................…………................13

5.1 Soft Flow Chart….………………..…………....….......13

5.2 Electrical Block Diagram….…...…………..….....…...15

SAFETY NOTICE

ANY PERSON ATTEMPTING TO SERVICE THIS CHASSIS MUST FAMILIARIZE HIMSELF WITH THE

CHASSIS AND BE AWARE OF THE NECESSARY SAFETY PRECAUTIONS TO BE USED WHEN SERVICING

ELECTRONIC EQUIPMENT CONTAINING HIGH VOLTAGES.

CAUTION: USE A SEPARATE ISOLATION TRANSFOMER FOR THIS UNIT WHEN SERVICING

6.Schematic……………....................................…17

6.1 Main Board.……...……..........................................17

6.2 Power Board..………..……..................................21

6.3 Audio Board..………..…….................................23

7.PCB Layout..……………….......................................24

7.1 Main Board…………….........................................24

7.2 Power Board…..………...................................26

7.3 Audio Board………….....................................28

7.4 Key Board…..……….....................................28

8. Maintainability……….......................................29

8.1 Equipments and Tools Requirement……..............29

8.2 Trouble Shooting..…….………..............................30

9. White-Balance, Luminance adjustment.............36

10. Monitor Exploded View……….……………............37

11. BOM List……….....................................................39

1

17” LCD Color Monitor AOC 712Sa

Revision List

Revision Date Revision History TPV Model

A00 Feb.-07-07 Initial Release T76CNMNQF6AO8P

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17” LCD Color Monitor AOC 712Sa

Important Safety Notice

Proper service and repair is important to the safe, reliable operation of all AOC Company Equipment. The service

procedures recommended by AOC and described in this service manual are effective methods of performing service

operations. Some of these service operations require the use of tools specially designed for the purpose. The

special tools should be used when and as recommended.

It is important to note that this manual contains various CAUTIONS and NOTICES which should be carefully read in

order to minimize the risk of personal injury to service personnel. The possibility exists that improper service

methods may damage the equipment. It is also important to understand that these CAUTIONS and NOTICES ARE

NOT EXHAUSTIVE. AOC could not possibly know, evaluate and advise the service trade of all conceivable ways in

which service might be done or of the possible hazardous consequences of each way. Consequently, AOC has not

undertaken any such broad evaluation. Accordingly, a servicer who uses a service procedure or tool which is not

recommended by AOC must first satisfy himself thoroughly that neither his safety nor the safe operation of the

equipment will be jeopardized by the service method selected.

Hereafter throughout this manual, AOC Company will be referred to as AOC.

WARNING

Use of substitute replacement parts, which do not have the same, specified safety characteristics may create shock,

fire, or other hazards.

Under no circumstances should the original design be modified or altered without written permission from AOC.

AOC assumes no liability, express or implied, arising out of any unauthorized modification of design.

Servicer assumes all liability.

FOR PRODUCTS CONTAINING LASER:

DANGER-Invisible laser radiation when open AVOID DIRECT EXPOSURE TO BEAM.

CAUTION-Use of controls or adjustments or performance of procedures other than those specified herein may

result in hazardous radiation exposure.

CAUTION -The use of optical instruments with this product will increase eye hazard.

TO ENSURE THE CONTINUED RELIABILITY OF THIS PRODUCT, USE ONLY ORIGINAL MANUFACTURER'S

REPLACEMENT PARTS, WHICH ARE LISTED WITH THEIR PART NUMBERS IN THE PARTS LIST SECTION OF

THIS SERVICE MANUAL.

Take care during handling the LCD module with backlight unit

-Must mount the module using mounting holes arranged in four corners.

-Do not press on the panel, edge of the frame strongly or electric shock as this will result in damage to the screen.

-Do not scratch or press on the panel with any sharp objects, such as pencil or pen as this may result in damage to

the panel.

-Protect the module from the ESD as it may damage the electronic circuit (C-MOS).

-Make certain that treatment person’s body is grounded through wristband.

-Do not leave the module in high temperature and in areas of high humidity for a long time.

-Avoid contact with water as it may a short circuit within the module.

-If the surface of panel becomes dirty, please wipe it off with a soft material. (Cleaning with a dirty or rough cloth may

damage the panel.)

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17” LCD Color Monitor AOC 712Sa

1. Monitor Specifications

Driving system TFT Color LCD

LCD Panel

Input

Display Colors 16.2M Colors

Dot Clock 135MHz

Max. Resolution 1280 × 1024

Plug & Play VESA DDC2BTM

EPA ENERGY STAR®

Input Connector 15-pin D-Sub

Input Video Signal

Maximum Screen Size

Power Source 100~240VAC,50~60Hz

Environmental

Considerations

Dimension 371(W)×380(H)×106.4(D)mm

Size 43.2cm(17.0")

Pixel pitch 0.264mm( H ) × 0.264mm( V )

Video R,G,B Analog Interface

Separate Sync. H/V TTL

H-Frequency 30kHz – 80kHz

V-Frequency 55-75Hz

ON Mode ≤37W

OFF Mode ≤1W

Analog:0.7Vp-p(standard),

75 OHM, Positive

Horizontal : 337.92mm

Vertical : 270.34mm

Operating Temp: 5° to 35°C

Storage Temp.: -20° to 60°C

Operating Humidity: 10% to 85%

Weight (N. W.) 4.5kg Unit (net)

Audio Output

Power Consumption( Maximum ) 37 Watts

Regulatory Compliance cULus, TUV-S

4

Rated Power 1.5 W rms

(Per channel)

17” LCD Color Monitor AOC 712Sa

2. LCD Monitor Description

The LCD monitor will contain a main board, a power board, a key board and an audio 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.

RS232 Connector

For white balance

adjustment in factory

mode

Video signal, DDC

HOST Computer

Power board

(Include: adapter, inverter)

AC-IN 100V-240V

Monitor Block Diagram

CCFL Drive.

Flat Panel and

CCFL backlight

Main Board

Key board Audio board

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17” LCD Color Monitor AOC 712Sa

3. Operating Instructions

3.1 General Instructions

Press the power button to turn the monitor on or off. The other control buttons are located at front panel of the

monitor. By changing these settings, the picture can be adjusted to your personal preferences.

• The power cord should be connected.

• Connect the video cable from the monitor to the video card.

• Press the power button to turn on the monitor position. The power indicator will light up.

3.2 Control Buttons

EXTERNAL CONTROLS

1. Auto Adjust Key/Exit 4. > / Volume

2. < / Volume 5. MENU/ENTER

3. Power Key/ LED

1. AC Power Cord

2. D-Sub Cable

3. Audio Cable

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17” LCD Color Monitor AOC 712Sa

FRONT PANEL CONTROL

• Power Button / Power Indicator:

Press this button to turn the monitor ON or OFF.

Blue — Power On mode.

Orange — Off mode.

• MENU / ENTER :

Activate OSD menu when OSD is OFF or activate/de-activate adjustment function when OSD is ON or Exit OSD

menu when in Volume Adjust OSD status.

• > /Volume:

Activates the volume control when the OSD is OFF or navigate through adjustment icons when OSD is ON or

adjust a function when function is activated.

• < /Volume:

Activates the volume control when the OSD is OFF or navigate through adjustment icons when OSD is ON or

adjust a function when function is activated.

• Auto Adjust button / Exit:

1. When OSD menu is in active status, this button will act as EXIT-KEY (EXIT OSD menu).

2. When OSD menu is in off status, press this button for 2 seconds to activate the Auto Adjustment function.

The Auto Adjustment function is used to set the HPos, VPos, Clock and Focus.

OSD Lock Function: To lock the OSD, press and hold the MENU button while the monitor is off and then press

power button to turn the monitor on. To un-lock the OSD - press and hold the MENU button while the monitor is

off and then press power button to turn the monitor on.

NOTES

• Do not install the monitor in a location near heat sources such as radiators or air ducts, or in a place subject to

direct sunlight, or excessive dust or mechanical vibration or shock.

• Save the original shipping carton and packing materials, as they will come in handy if you ever have to ship your

monitor.

• For maximum protection, repackage your monitor as it was originally packed at the factory.

• To maintain the cleanness of your LCD display, wipe it periodically with clean and soft cloth. The screen may be

damaged by any liquid splash.

• To keep the monitor looking new, periodically clean it with a soft cloth. Stubborn stains may be removed with a

cloth lightly dampened with a mild detergent solution. Never use strong solvents such as thinner, benzene, or

abrasive cleaners, since these will damage the cabinet. As a safety precaution, always unplug the monitor before

cleaning it.

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17” LCD Color Monitor AOC 712Sa

3.3 Adjusting the Picture

Press the MENU-button to activate the OSD window.

1. Press the MENU-button to activate the OSD window.

2. Press < or > to navigate through the functions. Once the desired function is highlighted, press the MENU-button

to activate it. If the function selected has a sub-menu, press < or > again to navigate through the sub-menu

functions. Once the desired function is highlighted, press MENU-button to activate it.

3. Press < or > to change the settings of the selected function.

4. To exit and save, select the exit function. If you want to adjust any other function, repeat steps 2-3.

The descriptions for function control LEDS

Main Menu

Item

Luminance

Image Setup

Image

Position

Color Temp.

Main Menu

Icon

Sub Menu

Item

Contrast

Brightness

Focus

Clock

H. Position

V. Posi t i o n

Warm N/A Recall Warm Color Temperature from EEPROM.

Cool N/A Recall Cool Color Temperature from EEPROM.

sRGB N/A Recall sRGB Temperature from EEPROM.

User / Red

User / Green

User / Blue

Ye s

No N/A Do not execute Auto Config, return to main menu.

Sub Menu

Icon

N/A Auto Adjust the H/V Position, Focus and Clock of picture. Auto Config

Contrast from Digital-register.

Adjust Picture Phase to reduce Horizontal-Line noise

Adjust picture Clock to reduce Vertical-Line noise.

Adjust the horizontal position of the picture.

Adjust the vertical position of the picture.

Red Gain from Digital-register.

Green Gain Digital-register.

Blue Gain from Digital-register.

Description

Backlight Adjustment

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17” LCD Color Monitor AOC 712Sa

Main Menu

Item

OSD Setup

Language

Information

Main

Menu Icon

Sub Menu

Item

Sub Menu Icon Description

H. Position

V. Posi t i o n

OSD Timeout

Language N/A Select the language you like.

Information N/A

Adjust the horizontal position of the OSD.

Adjust the vertical position of the OSD.

Adjust the OSD timeout.

Show the resolution, H/V frequency and input

port of current input timing.

Reset

Yes N/A Clear each old status of Auto-configuration.

Exit

No N/A Do not execute reset, return to main menu.

N/A N/A Exit OSD

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17” LCD Color Monitor AOC 712Sa

4. Input/Output Specification

4.1 Input Signal Connector

Pin No. Description Pin No. Description

1. Red Video 9. + 5V

2. Green Video 10. Detect Cable

3. Blue Video 11. Ground

4.

5.

6.

7.

8.

4.2 Factory Preset Display Modes

Standard

Dos-mode 720 x 400 31.47kHz 70.0Hz

Ground

R-Ground

G-Ground

B-Ground

Resolution

12. DDC-Serial Data

13. H-Sync

14. V-Sync

15. DDC-Serial Clock

Analog Connector

15

6

11 15

10

Horizontal Frequency

Vertical

Frequency

VGA

640 × 480 31.47kHz 60.0Hz

640 × 480 37.50kHz 75.0Hz

800 × 600 37.879kHz 60.0Hz

SVGA

800 × 600 46.875kHz 75.0Hz

1024 × 768 48.363kHz 60.0Hz

XGA

1024 × 768 56.476kHz 70.0Hz

1024 × 768 60.021kHz 75.0Hz

1280 × 1024 64.000kHz 60.0Hz

SXGA

1280 × 1024 80.000kHz 75.0Hz

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17” LCD Color Monitor AOC 712Sa

4.3 Panel Specification

CLAA170EA07P is 17.0” color TFT-LCD (Thin Film Transistor Liquid Crystal Display) module composed of LCD

panel, driver ICs, control circuit and backlight. By applying 8 bit digital data,1280×1024, 16.2M-color images are

displayed on the 17.0” diagonal screen. Input power voltage is 5.0V for LCD driving. Inverter for backlight is not

included in this module.

4.3.1 Display Characteristics

4.3.2 Optical Characteristics

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17” LCD Color Monitor AOC 712Sa

4.3.3 ELECTRICAL CHARACTERISTICS

TFT LCD Module:

Back Light Unit:

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17” LCD Color Monitor AOC 712Sa

Y

5. Block Diagram

5.1 Software Flow Chart

1

2

4

5

6

7

9

10

N

3

N

11

N

12

13

N

16

18

N

14

19

15

17

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17” LCD Color Monitor AOC 712Sa

1) MCU initializes.

2) Is the EPROM blank?

3) Program the EPROM by default values.

4) Get the PWM value of brightness from EPROM.

5) Is the power key pressed?

6) Clear all global flags.

7) Are the AUTO and SELECT keys pressed?

8) Enter factory mode.

9) Save the power key status into EPROM.

Turn on the LED and set it to green color.

Scalar initializes.

10) In standby mode?

11) Update the lifetime of back light.

12) Check the analog port, are there any signals coming?

13) Does the scalar send out an interrupt request?

14) Wake up the scalar.

15) Are there any signals coming from analog port?

16) Display "No connection Check Signal Cable" message. And go into standby mode after the message

disappears.

17) Program the scalar to be able to show the coming mode.

18) Process the OSD display.

19) Read the keyboard. Is the power key pressed?

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17” LCD Color Monitor AOC 712Sa

(

)

5.2 Electrical Block Diagram

5.2.1 Main Board

Keypad Interface

(CN403)

Panel Interface

(CN406)

NT68623MEFG-64/G

(Include MCU, ADC, OSD)

(U401)

SDA SCL

EEPROM

AT24C16AN-10SU-2.7

U403)

Crystal 12MHz

(X401)

RXD

RGB

TXD

D-Sub Connector

(CN405)

DB15_SDA DB15_SCL

EEPROM

M24C02-WMN6TP

U405

H-SYNC V-SYNC

15