AOC M2752PQU User manual

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Service
Service
Service
Horizontal Frequency
30-83 KHz
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.
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.Hotkeys…………….…..............……...............6
3.3.OSD Menu…………….…...........................…............7
4.Input/Output Specification............……………............21
4.1.Input Signal Connector............………….................20
4.2.Power Supply Requirements...............................22
4.3.Factory Preset Display Modes……..........................22
4.4.Panel Specification.....………...…………..................23
5.Block Diagram…..….....................…………................25
5.1.Main Board………..…………………....….......26
5.2.Power Board……………..……………..….......26
6.Schematic……………......................................27
6.1.Main Board………..........................................27
6.2.Power Board...….…....................................39
6.3Key Board……….……………………………41
6.4USB Board……….……………………………42
7.PCB Layout..………….......................................44
7.1.Main Board………........................................44
7.2.Power Board….......................................46
7.3.Key Board…………….....................................48
7.4.USB Board………….....................................49
8.Maintainability……….......................................50
8.1.Equipments and Tools Requirement...............50
8.2.Trouble Shooting…………..............................51
9.White-Balance, Luminance Adjustment.............55
10.Monitor Exploded View………..…….…............57
11.BOM List………………………………............59
CAUTION: USE A SEPARATE ISOLATION TRANSFOMER FOR THIS UNIT WHEN SERVICING

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Revision List
Version Release Date Revision History TPV Model Name
A00 Oct.25.2012 Initial release HFCAT16BEEK2DN

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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 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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1. Monitor Specifications

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2. LCD Monitor Description
The LCD monitor will contain a main board, a power board and a 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.
AC-IN
100V-240V
Monitor Block Diagram
Power board
(
Include: ada
p
ter
,
inverter
)
Flat Panel and
LED backlight
Main Board RS232 Connector
For white balance
adjustment in factory
mode
LED Drive.
Video signal, DDC
Key Board
HOST Computer

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3. Operating Instructions
3.1 General Instructions
Press the power button to turn the monitor on or off. The other control knobs are located at a grounded panel of the
monitor. By changing these settings, the picture can be adjusted to your personal preferences.
3.2 Hotkeys
Power Press the Power button to turn on/off the monitor.
Eco (DCR)/ - Press the Eco key continuously to select the Eco mode of brightness and DCR on when there is no
OSD. ( Eco mode hot key may not be available in all models).
Volume/+ When there is no OSD,Press Volume button to active volume adjustment bar,Press - or + to adjust
volume.(Only for the models with speakers)
Auto/Exit When there is no OSD, press Auto/Source button continuously about 3 second to do auto configure.
Source hot key When the OSD is closed, press Source button will be Source hot key function. Press Source button
continuously to select the input source showed in the message bar , press Menu/Enter button to change to the
source selected.

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3.3 OSD Menu
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 . press - or + 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. Press AUTO to exit. If you want to adjust any other
function, repeat steps 2-3.
4) 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:
1) If the product has only one signal input, the item of "Input Select" is disable to adjust.
2) If the product screen size is 4:3 or input signal resolution is wide format, the item of "Image Ratio" is disable to
adjust.
3) One of DCR, Color Boost, and Picture Boost functions is active, the other two function is turned off accordingly.

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4. Input/Output Specification
4.1 Input Signal Connector
Analog connectors
Pin Numbe
r
15-Pin Side of the Si
g
nal Cable
1 Video-Red
2 Video-Green
3 Video-Blue
4 N.C.
5 Detect Cable
6 GND-R
7 GND-G
8 GND-B
9 +5V
10 Ground
11 N.C.
12 DDC-Serial data
13 H-sync
14 V-sync
15 DDC-Serial clock
DVI connectors
Pin No. Signal Name Pin No. Signal Name Pin No. Signal Name
1 TMDS Data 2- 9 TMDS Data 1- 17 TMDS Data 0-
2 TMDS Data 2+ 10 TMDS Data 1+ 18 TMDS Data 0+
3 TMDS Data 2/4 Shield 11 TMDS Data 1/3 Shield 19 TMDS Data 0/5 Shield
4 TMDS Data 4- 12 TMDS Data 3- 20 TMDS Data 5-
5 TMDS Data 4+ 13 TMDS Data 3+ 21 TMDS Data 5+
6 DDC Clock 14 +5V Power 22 TMDS Clock Shield
7 DDC Data 15 Ground(for+5V) 23 TMDS Clock +
8 N.C. 16 Hot Plug Detect 24 TMDS Clock -