AOC 201S Schematic

20" LCD Color Monitor AOC 201S

kHz

Service

Horizontal Frequency

30 kHz - 82

TABLE OF CONTENTS

Description

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

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

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

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

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

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

3.2. Control Buttons.……….…..............……...............6

3.3 Adjusting the Picture...........................…............7

4. Input/Output Specification............……………............9

4.1. Input Signal Connector............………….................9

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

4.3. Power Supply Requirements...............................10

5. Panel Specification.....………………..................11

5.1. General Feature…….....………………..................11

5.2. Optical Characteristics……………………….………12

6. Block Diagram……...................…………................13

Page Description Page

6.1 Software Flow Chart……..……………………….13

6.2. Electrical Block Diagram…….……………..….......15

7. Schematic……………......................................17

7.1 Main Board....……….......................................17

7.2 Power Board.….……....................................23

7.3 Key Board………………….……………………25

8. PCB Layout..………….......................................26

8.1. Main Board……….............................................26

8.2. Power Board….....................................................28

8.3. Key Board………............….......................30

9. Maintainability……….......................................31

9.1. Equipments and Tools Requirement..............31

9.2.Trouble Shooting………..............................32

10.White-Balance, Luminance adjustment……....38

11 Monitor Exploded View…………………....….......40

12. BOM List……...……………………………………41

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

SAFETY NOTICE

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20" LCD Color Monitor AOC 201S

Revision List

Version Date Revision History TPV Model Name

A00 Apr.-15-07 Initial release TA6MM5DBACA2N

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20" LCD Color Monitor AOC 201S

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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20" LCD Color Monitor AOC 201S

Weight (monitor only)

1. Monitor Specification

Items Description

Driving system TFT Color LCD Size 51cm (20”) Panel M201P1-L03

Display area 432.5(H) x332.0 (V) Pixel pitch 0.2916mm(H) x 0.2916mm(V)

LCD Panel

Input

Max. Resolution 1400 x 1050 @60 Hz Plug & Play VESA DDC1/2BTM

Power Consumption

Viewable angle 160˚ (H) 160˚ (V) Response time (typ.) 5ms Brightness 300cd/m² Contrast 1000:1 Dot Clock 162MHz Display Colors 16.7M Input Video Signal Analog: 0.7Vp-p(standard), 75 OHM, Positive

H-Frequency 30kHz – 82kHz V-Frequency 60-75Hz

ON Mode OFF Mode

≤41W ≤1W

6.3 kg

Dimensions 445.6(W) x 416.6(H) x 190.8(D)mm Power Source 100~240VAC,47~63Hz

6.3 kg

Environmental Considerations

Regulations

Operating Temp: 0°C to 35°C Storage Temp.: -20°C to 60°C Operating Humidity : 10% to 85%

CCC/cUL/FCC/CE/TCO03/TUV-GS/EPA

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20" LCD Color Monitor AOC 201S

(Include adapter and inverter)

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.

Monitor Block Diagram

Flat Panel and CCFL backlight

RS232 Connector For white balance adjustment in factory mode

Video signal, DDC

HOST Computer

Power Board

AC-IN 110V-240V

CCFT Drive.

Main Board

Key board

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20" LCD Color Monitor AOC 201S

3. Operation Instructions

3.1 General Instructions

Press the power button to turn the monitor on or off. The other control buttons are located at front of the panel. By changing these settings, the picture can be adjusted to your personal performance.

The power cord should be connected and insert to adaptor.

-

Connect the video cable from the monitor to the computer VGA card.

-

- Press the power button to turn on the monitor, the power indicator will light up to Green.

3.2 Front Panel Control

1.Exit/DDC-CI

2. Auto Config

3. Eco Mode/ +

4. Luminance/ -

5. Menu / Enter

6. Power Button & Indicator

LED Indicators

Status LED Color

Full Power Mode Green Active-off Mode Orange

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20" LCD Color Monitor AOC 201S

3.3 Adjust the Picture

OSD Settings

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

• 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.

• Press+ or - to change the settings of the selected function. To exit and save, select the exit function. If you want to adjust any other function, repeat steps 2-3.

• 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.

• Press Auto Config key continually for 7 sec. to turn on or off DDC-CI.

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20" LCD Color Monitor AOC 201S

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20" LCD Color Monitor AOC 201S

4. Input/Output Specification

4.1 Input Signal Connector

Analog connector

Pin Signal Pin Signal

1 Red Video 9 2 Green Video 3 Blue Video 4 N.C. 5 DDC Return 6 Red GND 14 Vertical Sync

7 Green GND 15 DDC-Serial Clock 8 Blue GND

15 - Pin Color Analog Signal Cable

VGA connector layout

10 GND 11 N.C. 12 DDC-Serial Data 13 Horizontal Sync

+5V

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20" LCD Color Monitor AOC 201S

4.2 Factory Preset Display Modes

4.3 Power Supply Requirements

A/C Line voltage range A/C Line frequency range Current : 5.0A max Peak surge current : < 55A peak at 240 VAC and cold starting Leakage current : < 3.5mA Power line surge : No advance effects (no loss of information or defect)

DC output Voltage current : 2Amp (5V); 3Amp (12V)

: 100 V ~ 240 V ±10％ : 50 ± 3Hz, 60 ± 3Hz

with a maximum of 1 half-wave missing per second : 5VDC ± 5％; 12VDC± 5％

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20" LCD Color Monitor AOC 201S

5. Panel Specification

5.1 General Feature

Mechanical Information

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20" LCD Color Monitor AOC 201S

5.2 Optical Characteristics

5.2.1 Test Conditions

5.2.2 Optical Specifications

The relative measurement methods of optical characteristics are shown

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20" LCD Color Monitor AOC 201S

1

2

5

10

12

7

6

4

3

8

9

14

11

13

15

16

17

19

18

6. Block Diagram

6.1 Software Flow Chart

Y

N

Y

N

Y

N

Y

N

Y

N

Y

N

Y

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20" LCD Color Monitor AOC 201S

Signal Cable" message. And go into standby mode after the message

REMARK:

1) MCU initialize.

2) Is the EEprom blank?

3) Program the EEprom by default values.

4) Get the PWM value of brightness from EEprom.

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 EEprom. Turn on the LED and set it to green color. Scalar initialize.

10) In standby mode?

11) Update the lifetime of back light.

12) Check the analog port, are they’re 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

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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20" LCD Color Monitor AOC 201S

6.2 Electrical Block Diagram

6.2.1 Main Board

LCD Interface

(CN101)

Flash Memory

PM25LV512-25SCE

(U402)

Key Board

Control

(CN403)

Scalar IC TSUM16AK-LF-1

(Include MCU, ADC, OSD)

Crystal

14.318MHz (X401)

(U401)

H sync V sync

RGB

D-Sub

Connector

(CN405)

SCL_VGA, SDA_VGA

EEPROM

M24C16

(U403)

EEPROM

M24C02

(U404)

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20" LCD Color Monitor AOC 201S

6.2.2 Inverter / Power Board

AC inlet Filter

On/off control

Rectifier and filter

Start circuit R904, R931, R938

Switching circuit PWM control IC&MOSFET

Start circuit

Transform

OVP/OCP circuit

Rectifier and filter D908, D909

Feedback circuit IC902, IC903

12V/5V

To main board

12V

Dimming control

PWM control IC

Push-pull

circuit

LC resonant

Feedback circuit

Lamp

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