Service manual

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1. Interface Board
1.1 Power Supply (DC/DC Converter)
IC100 is a linear regulator that converts a 12V DC input voltage into regulated and stable
output voltages of 5V respectively.
1.2 Micro-Controller
IC400 (scalar) built-in an micro-controller and an extra flash ROM (IC402---39SF010). It plays a
major role in the digital control of the LCD monitor. IC400 acts as a Key control, DPMS power
saving control, auto-detect controller, and controller of IC400 to do image process.
Pin 114 controls Inverter enable or disable
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Confidential – Do Not Copy VX900-2
Pin 113 enable vcc for panel
Pin 125 send a HI signal when audio is invalid
send a LOW signal when audio is valid
Pin 5 receive HI signal from IC401 pin 3 to reset
Pin 1,4, 39, 43, 46, 47, 125, 206 make key function operate when press key button (receive
LOW signal from key button.)
Pin 51, 52 communicate with IC404 (EEPROM) by I
2
C
Pin 48 detect audio in
Pin 44,45 do ISP(in-system program)
Pin 40 controls the brightness of panel
Pin 41, 42 controls LED (orange and green) on /off
Pin 123 control audio boards 12V on/off
Pin 126 control IC500, IC501(LVDS Transmitter) on/off.