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15" LCD Color Monitor Lenovo LXM-L15DB
Service
Service
Service
Horizontal Frequency
30-60KHz
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.OSD Menu…………….…...........................…............7
4.Input/Output Specification............…………….............10
4.1.Input Signal Connector.............………….................10
4.2.Factory Preset Display Modes..........................10
4.3.Panel Specification.....………………..................11
5.Block Diagram…..…...................…………................13
5.1.Software Flow Chart……..…………………...….......13
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SAFETY NOTICE
5.2.Electrical Block Diagram…………………......15
6.Schematic……………......................................17
6.1Main Board.............................................17
6.2Power Board....……........................................22
7.PCB Layout..………….......................................24
7.1.Main Board………........................................24
7.2.Power Board……….....................................25
7.3.Key Board…………….....................................26
8.Maintainability……….......................................26
8.1.Equipments and Tools Requirement...............26
8.2.Trouble Shooting…………..............................27
9.White-Balance, Luminance adjustment.............33
10.Monitor Explode View………..…….…............35
11.BOM List…………………………………............36
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
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15" LCD Color Monitor Lenovo LXM-L15DB
Revision List
Version Release Date Revision History TPV Model Name
A00 Jun.06, 2007 Initial release
T56VM2MCA8GNNJ
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15" LCD Color Monitor Lenovo LXM-L15DB
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
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damage the panel.)
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15" LCD Color Monitor Lenovo LXM-L15DB
1. Monitor Specifications
Driving system TFT Color LCD
LCD Panel
Input
Display Color
Dot Clock 80MHz
Max. Resolution 1024 x 768
Plug & Play
Input Connector D-Sub 15pin
Input Video Signal
Maximum Screen Size
Size 38.0cm(15")
Pixel pitch 0.297mm( H )x 0.297mm( V )
Video R,G,B Analog Interface
Separate Sync. H/V TTL
H-Frequency 30kHz – 60kHz
V-Frequency 50Hz -75Hz
16.7M Colors
VESA DDC2B
Analog:0.7Vp-p(standard),
75OHM,Postive
Horizontal : 304.128mm
Vertical: 228.096mm
TM
,DDC/CI
Power Source AC100~240V,47~63Hz
Environmental
Considerations
Weight(N.W.) 2.8kg
Power Consumption ≤30W
Regulatory Compliance FCC, CE, CCC, CSC
Operating Temp:10°C to 40°C(-32°F to 104°F)
Storage Temp: -20°C to 60°C(-4°F to 104°F)
Operating Humidity: 10% to 85%
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15" LCD Color Monitor Lenovo LXM-L15DB
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.
Power board
Include: adapter, inverter)
AC-IN
100V-240V
Monitor Block Diagram
CCFL Drive.
Key Board
Flat Panel and
CCFL backlight
Main Board
HOST Computer
RS232 Connector
For white balance
adjustment in factory
mode
Video signal, DDC
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15" LCD Color Monitor Lenovo LXM-L15DB
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 the front of the
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, the power indicator will light up.
-
3.2 Control Buttons
3.2.1 Key Control
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15" LCD Color Monitor Lenovo LXM-L15DB
3.2.2 Key Function
3.3 OSD Menu
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15" LCD Color Monitor Lenovo LXM-L15DB
OSD functions
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15" LCD Color Monitor Lenovo LXM-L15DB
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15" LCD Color Monitor Lenovo LXM-L15DB
4. Input/Output Specification
4.1 Input Signal Connector
Analog connectors
Pin No. Description Pin No. Description
1. Red 9. +5VDC
2. Green 10. Connect Check
3. Blue 11. GND
4. GND 12. DDC-Serial Data
5. GND 13. H-Sync
6. Red GND 14. V-Sync
7. Green GND 15. DDC-Serial Clock
8. Blue GND
VGA connector layout
15
6
11 15
10
4.2 Factory Preset Display Modes
Standard
Dos-Mold
VGA
SVGA
XGA
Resolution
720x400
640x480
640x480
640x480
800x600
800x600
800x600
800x600
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1024x768
1024x768
1024x768
Horizontal
Frequency(KHz)
31.47 70
31.47
31.86
31.50
35.16
37.88
48.08
46.88
48.36 60
56.48
60.02
Vertical
Frequency(Hz)
60
72
75
56
60
72
75
70
75
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15" LCD Color Monitor Lenovo LXM-L15DB
4.3 Panel Specification
4.3.1 Display Characteristics
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15" LCD Color Monitor Lenovo LXM-L15DB
4.3.2 Optical Characteristics
4.3.3 Electrical Characteristics
(1) TFT-LCD
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(2) Backlight
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15" LCD Color Monitor Lenovo LXM-L15DB
5. Block Diagram
5.1 Software Flow Chat
1
2
N
4
5
Y
6
7
Y
N
N
3
9
10
Y
N
12
Y
N
11
13
N
Y
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N
16
18
14
N
19
15
Y
17
Y
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15" LCD Color Monitor Lenovo LXM-L15DB
1) MCU initialize.
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
disappear.
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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