Saturday, January 16, 2016

AOC LM2028 – 20 inch LCD Monitor – service mode – EDID data – SMPS schematic

Used ICs: LM358 – FP5001DR – TL1451ACNSR – SG6841 – ST9NK60ZF(FET)
20.1 inch Color TFT-LCD
ALL input signals are 2 Channel LVDS interface compatible
Supports the SXGA(H1600Pixel × V1200Lines) resolution
By applying 16.7M colors (RGB 8 bit data)
This module does not contain an inverter card for back light.
SERVICE MODE
 Turn off the power and remove the power plug, then press the menu key and plug in at the same time, finally, press the menu again will activate the factory mode, the factory OSD will be at the left top of the screen.
WHITE- BALANCE, LUMINANCE ADJUSTMENT
Approximately 30 minutes should be allowed for warm up before proceeding White-Balance adjustment.
1
How to do the Chroma-7120 MEM. channel setting
A Reference to chroma 7120 user guide
B Use “ SC” key and “ NEXT” key to modify xyY value and use “ID” key to modify the TEXT description Following is the procedure to do white-balance adjust
2 Setting the color temp. you want
A MEM.CHANNEL 3 ( 7800 color):
7800 color temp. parameter is x = 296 ±10, y = 311 ±10, Y = 200 ±10 cd/m2 ,
B MEM.CHANNEL 4 ( 6500 color): 6500 color temp. parameter is x = 313±10, y = 329 ±10, Y = 200 ±10 cd/m2)
3 Enter into the factory preset mode of LM2028.
4 Bias adjustment :
Set the Contrast to 50 Adjust the Brightness to 80.
5
Gain adjustment :
Move cursor to “-F-” and press MENU key
A Adjust C2(7800) color-temperature
1 Switch the Chroma-7120 to RGB-Mode (with press “MODE” button )
2 Switch the MEM. channel to Channel 3 (with up or down arrow on chroma 7120)
3 The LCD-indicator on chroma 7120 will show x = 296 ±10, y = 311 ±10, Y = 200 ±10 cd/m2
4 Adjust the RED of color1 on factory window until chroma 7120 indicator reached the value R=100
5 Adjust the GREEN of color1 on factory window until chroma 7120 indicator reached the value G=100
6 Adjust the BLUE of color1 on factory window until chroma 7120 indicator reached the value B=100
7 Repeat above procedure ( item 4,5,6) until chroma 7120 RGB value meet the tolerance =100±2
B Adjust C1(6500) color-temperature
1 Switch the chroma-7120 to RGB-Mode (with press “MODE” button )
2 Switch the MEM .channel to Channel 4( with up or down arrow on chroma 7120 )
3 The LCD-indicator on chroma 7120 will show x = 313 ±10, y = 329 ±10, Y = 200 ±10 cd/m2
4 Adjust the RED of color3 on factory window until chroma 7120 indicator reached the value R=100
5 Adjust the GREEN of color3 on factory window until chroma 7120 indicator reached the value G=100
6 Adjust the BLUE of color3 on factory window until chroma 7120 indicator reached the value B=100
7 Repeat above procedure ( item 4,5,6) until chroma 7120 RGB value meet the tolerance =100±2
C Press reset key and Turn the Power-button “off to on” to quit from factory mode.
POWER - SMPS - Circuit Diagram
EDID DATA
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