AOC L19W831 Schematic

19″LCD TV AOC L19W831

Service

43~58 kHz

TABLE OF CONTENTS

Description Page Description Page

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

Important Safety Notice.......................................……......2

Revision List…………………………………………………3

1. General Specification..............................………........4

2. Operating Instructions…………………….……….......5

2.1. The Use Of Remote Control…….………….…….......5

2.2. To Use The Menu…...…………………….……….......6

2.3. How To Connect…….…………………….……….....11

2.4. Front Panel Control Knobs……………….……….....13

3. Input/Output Specification…………....................…....14

4. Mechanical Instructions…………………….................16

5. Repair Flow Chart ……………………….…….…….....19

6. PCB Layout ………………..………………....….......24

SAFETY NOTICE

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

6.1.Main Board…………..……………...……….......24

6.2.Power Board……………..………….……….......27

6.3.Key Board………………………..……….......28

6.4.IR Board…………………………..……….......28

7. White-Balance, Luminance Adjustment...................29

8. Block Diagram.……...........................................30

9. Schematic……………...…………..………………...31

9.1 Main Board…………………………………...….......31

9.2.Power Board…………….…………...………….......42

9.3.Key Board……………….……….………….......44

10. Exploded View………………………………….…...45

11. BOM List……………….…………………………….46

Horizontal Frequency

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

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19″LCD TV AOC L19W831

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 might 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 radiations 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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19″LCD TV AOC L19W831

Revision List

Version Release Date Revision Instructions TPV Model

A00 Jun.-14-2008 Initial Release E198MANSW8AC3N

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19″LCD TV AOC L19W831

1. General Specification

Items Specification

Panel Type M190A1-L0A C1 TW panel

Driving system TFT-LCD CMO Panel

Aspect Ratio 16: 10

Resolutions 1440 x 900

LCD Panel

TV Function

Video Inputs

Audio Output Audio Output: L / R

OSD language English, etc

Wall Mount VESA 100 mm x 100 mm

Power

Brightness

Contrast 800:1

Pixel Pitch 0.2835mm x0.2835mm

Display colors 16.2 million

Color Temperature Cool / Warm/normal

TV Standard NTSC-M/PAL-M/PAL-N

Color systems NTSC-M/PAL-M/PAL-N

AV RCA x 1 Audio L/R x 1

S-Video S-Video x 1 Audio L/R x 1

COMPONENT Y,Cb,Cr x 1 Audio channel L / Rx 1

HDMI 720p,1080i,480p,480i

Power Supply AC100V~240V, 50/60Hz

Power Consumption

250 cd/㎡

Speaker (built-in): Two 3W speakers

Headphone Mini-jack for stereo (3.5ø)

< 75W

<1W (in standby mode)

Environment

Operating 5 °C ~ 40 °C

Storage 0 °C ~ 50 °C

Operating 10% ~ 85%

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19″LCD TV AOC L19W831

2. Operating Instructions

2.1 The Use of Remote Control

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19″LCD TV AOC L19W831

2.2 To Use the Menus

MAIN MENU

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19″LCD TV AOC L19W831

2.3 How to Connect

Connecting your TV to a power outlet

• Plug the power cord into a power outlet.

Connecting an outside antenna

Antenna cables come in two types: 75 ohm and 300 ohm.

• If your antenna cable has a 75 ohm connector, connect the cable to the coaxial jack on the back of your TV.

• If your antenna cable has a 300 ohm connector, connect the cable to a 300-75 ohm adapter (not included), connect

the adapter to a 75 ohm cable, then connect the other end of the 75 ohm connector to the coaxial jack on the back of

your TV.

To connect cable TV without a converter/descrambler box:

1 Connect one end of a 75 ohm cable to the coaxial jack on the back of your TV.

2 Connect the other end of the cable to the cable TV wall outlet.

To connect cable TV with a converter/descrambler box:

• Use the following illustration to connect a converter/descrambler box. (The RF switch and the signal splitter are not

provided.) Set the RF switch to the A position to watch unscrambled channels using your TV remote control. Set the

RF switch to the B position to watch scrambled channels using the converter/descrambler controls.

To connect an external signal source:

1 For composite video—plug the audio/video cable into the AV IN L and R jacks (6), and AV IN VIDEO (4) jacks

on the back of your TV, then connect the other ends to the corresponding jacks on the external signal source- OR

–For S-Video—Plug in the audio cables as described above, then plug one end of an S-Video cable into the AV IN

S-Video(5) jack on the back of your TV and the other end into the S-Video jack on external signal source.

- OR - For component video—Plug the Y, Pb, and Pr video (3)cables into the component input jacks, and the

Audio L and Audio R cables into the COMPONENT (2) audio jacks on the back of your TV, then plug the other ends

of the cables into the corresponding jacks on the external signal source.

- OR - For HDMI—plug one end of an HDMI (1) cable into the back of the TV and the other end into an HDMI device.

2 Turn on your TV.

3 Press the INPUT to open the input source menu, press v or ^ to select the external signal source you want to

watch, and then press ENTER.

4 Turn on external signal source.

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19″LCD TV AOC L19W831

5 Insert a disc or videotape into the external signal source, and then press the PLAY button.

To connect a computer using VGA:

1 Plug a VGA cable from your computer into the VGA jack on the back of your TV.

2 Plug an audio cable from your computer’s audio out jack into the AUDIO jack on the back of your TV.

3 Plug in and turn on your TV.

4 Press the INPUT to open the input source menu, press v or ^ to select VGA, and then press ENTER.

To connect a computer using HDMI:

• Plug an HDMI cable into the HDMI INPUT jack on the back of your TV and into the HDMI Out jack on the back of

the computer.

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19″LCD TV AOC L19W831

2.4 Front Panel Control Knobs

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3. Input/Output Specification

3.1 RGB Signal input

15 - Pin Color Display Signal Cable

Pin No. Description Pin No. Description

1 Red Video 9 Mandatory +5V Supply for PC Bypass

2 Green Video 10 Sync Ground

3 Blue Video 11 SDA(Remote Control)

4 SCL(Remote Control) 12 Bi-directional Data (SDA) for PC Bypass

1

6

11 15

5

10

5 Ground 13 H-Sync.

6 Red Video Ground 14 V-Sync.

7 Green Video Ground 15 Data Clock (SCL) for PC Bypass

8 Blue Video Ground

3.2 HDMI Digital connector pin assignments

Pin No. Description Pin No. Description

1 TMDS Data2+ 2 TMDS Data2 Shield

3 TMDS Data2- 4 TMDS Data1+

5 TMDS Data1 Shield 6 TMDS Data1-

7 TMDS Data0+ 8 TMDS Data0 Shield

9 TMDS Data0- 10 TMDS Clock+

11 TMDS Clock Shield 12 TMDS Clock-

13 CEC 14 NC

15 SCL 16 SDA

17 DDC/CEC Ground 18 +5V Power

19 Hot Plug Detect

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19″LCD TV AOC L19W831

3.3 AV/S-Video/Component Video Inputs

AV (Composite Video input)

Video1

Amplitude 1.0 V (p-p), negative sync.

Impedance 75 ohm terminated

S-Video (Y / C input)

S-Video2

System NTSC

Y signal amplitude 1.0Vpp (including sync)

C signal amplitude 0.286Vpp

Impedance 75 ohm terminated

Component (Y, Pb/Cb, Pr/Cr input)

Video3

Y signal amplitude 1.0Vpp (including sync)

Impedance 75 ohm terminated

3.4 Compatible Mode Table

System NTSC

System 1080i, 480p, 720p, 480i

Cr, (R-Y) / Cb, (B-Y)

Signal amplitude

VESA MODES

±0.35Vpp, 75 ohm

Horizontal Vertical

Nominal

Pixel

Clock

(MHz)

Mode Resolution Total

640x480@60Hz 800 x 525 31.469 N 59.940 N 25.175

VGA

SVGA

XGA

640x480@72Hz 832 x 520 37.861 N 72.809 N 31.500

640x480@75Hz 840 x 500 37.5 N 75 N 31.500

720x400@70Hz 900 x 449 31.469 N 70.087 P 28.322

800x600@56Hz 1024 x 625 35.156 P 56.25 P 36.000

800x600@60Hz 1056 x 628 37.879 P 60.317 P 40.000

800x600@72Hz 1040 x 666 48.097 P 72.188 P 40.000

800x600@75Hz 1056 x 625 46.875 P 75 P 49.5

1024x768@60Hz 1344x806 48.363 N 60.004 N 65.000

1024x768@70Hz 1328x806 56.476 N 70.069 N 75.000

1024x768@75Hz 1312x800 60.023 P 75.029 P 78.750

Nominal

Frequency

(KHz)

Sync

Polarity

Nominal

Freq.

(Hz)

Sync

Polarit

y

WXGA

1360x768@60Hz 1792x795 47.712 P 60.015 P 85.5

1440x900@60Hz 1600x926 55.469 P 59.901 N 88.75

1440x900@60Hz 1904x934 55.935 N 59.887 P 106.5

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19″LCD TV AOC L19W831

4. Mechanical Instructions

1. Remove the 3 screws to remove the stand base.

2. Remove 7 screws to remove the rear cover.

3. Remove speakers & key board.

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19″LCD TV AOC L19W831

4. Remove the screws & connectors to remove the main board, power board.

5. Remove the bezel.

6. Remove IR board.

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7. Remove the 4 screws to remove the main frame.

8. The panel.

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19″LCD TV AOC L19W831

5. Repair Flow Chart

1. No Power (No LED indicator)

Check power cord and board interface

OK

NG

Plug in power cord and interface

Check F901, BD901, C905

OK

Check IC901, Q901

OK

Check T901

OK

Check D904, D906

OK

Check ZD920

NG

2. Can not start (LED indicator yellow)

Can not start

NG

Replace ZD920

Replace F901 or BD901 or C905

Replace IC901 or Q901

Replace T901

Replace D904 or D906

OK

Check key board or remote control

OK

Check U701, U702, U703

OK

Check U400

OK

Check I2C communication

NG

Replace U400

Repair key board or remote control

Replace U701, U702, U703

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19″LCD TV AOC L19W831

UH200

3. No display (LED indicator green)

Check back light is OK

OK

Check LVDS cable

and connector

OK

Check UH200

OK

Check U202

NG

OK

Check Panel

Replace

Replace U202

Check 12V

power supply

OK

Check BL-ON/OFF signal

NG

Replace Panel

NG

Check Q705、Q706

Check PS

signal

NG

OK

Replace Q705、Q706

Check power

board

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