AOC L19W831 User manual

19″LCDTV AOC L19W831
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Service
Service
Service
Horizontal Frequency
43~58kHz
TABLE OF CONTENTS
Description Page Description Page
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
6.1.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
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

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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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Revision List
Version Release Date Revision Instructions TPV Model
A00 Jun.-14-2008 Initial Release E198MANSW8AC3N

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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
Brightness 250 cd/㎡
Contrast 800:1
Pixel Pitch 0.2835mm x0.2835mm
Display colors 16.2 million
LCD Panel
Color Temperature Cool / Warm/normal
TV Standard NTSC-M/PAL-M/PAL-N
TV Function
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
Video Inputs
HDMI 720p,1080i,480p,480i
Speaker (built-in): Two 3W speakers
Audio Output Audio Output: L / R Headphone Mini-jack for stereo (3.5ø)
OSD language English, etc
Wall Mount VESA 100 mm x 100 mm
Power Supply AC100V~240V, 50/60Hz
< 75W
Power Power Consumption <1W (in standby mode)
Operating 5 °C ~ 40 °C
Storage 0 °C ~ 50 °C
Environment
Operating 10% ~ 85%

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2. Operating Instructions
2.1 The Use of Remote Control

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MAIN MENU
2.2 To Use the Menus

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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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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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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
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
1
6
11 15
5
10

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3.3 AV/S-Video/Component Video Inputs
3.4 Compatible Mode Table
VESA MODES
Horizontal Vertical
Mode Resolution Total
Nominal
Frequency
(KHz)
Sync
Polarity
Nominal
Freq.
(Hz)
Sync
Polarit
y
Nominal
Pixel
Clock
(MHz)
640x480@60Hz 800 x 525 31.469 N 59.940 N 25.175
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
VGA
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
SVGA
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
XGA
1024x768@75Hz 1312x800 60.023 P 75.029 P 78.750
1360x768@60Hz 1792x795 47.712 P 60.015 P 85.5
1440x900@60Hz 1600x926 55.469 P 59.901 N 88.75
WXGA
1440x900@60Hz 1904x934 55.935 N 59.887 P 106.5
AV (Composite Video input)
Video1
System NTSC
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
System 1080i, 480p, 720p, 480i
Y signal amplitude 1.0Vpp (including sync)
Cr, (R-Y) / Cb, (B-Y)
Signal amplitude ±0.35Vpp, 75 ohm
Impedance 75 ohm terminated

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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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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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5. Repair Flow Chart
1. No Power (No LED indicator)
2. Can not start (LED indicator yellow)
NG Re
p
air ke
y
board or remote control
OK
Check U701
,
U702
,
U703 NG Re
p
lace U701
,
U702
,
U703
Check U400 NG Re
p
lace U400
OK
OK
Check ke
y
board or remote control
Check I
2
C communication
Can not start
OK
NG
Check power cord and board interface Plug in power cord and interface
OK
Check F901, BD901, C905 NG Replace F901 or BD901 or C905
OK
Check IC901, Q901
Check D904, D906
NG Replace IC901 or Q901
OK
Check T901
OK
Replace T901
Replace D904 or D906
OK
NG
NG
Check ZD920 NG Replace ZD920

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3. No display (LED indicator green)
Check 12V
power supply
Check Panel NG Replace Panel
Check back light is OK
OK
Check LVDS cable
and connector
OK
Check UH200 NG Replace
U
H2
00
OK
Check U202 NG Replace U202
NG NG
OK
Check BL-ON/OFF signal
Check PS
signal
OK
OK Check power
board
NG
NG
NG
Check Q705、Q706 Replace Q705、Q706
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