Service manual

returned to this pin.

Pin5 (SW) are switch node connections to inductors. In step-down applications the voltage

swing at this pin from a schottky diode (DM1) drops below ground to VIN.

Pin6 (TG) is the output of a floating drive for top N-channel MOSFET (ICM2).This is the

output of a floating drive with a voltage swing equal to INTV

CC superimposed on the switch

node voltage SW.

Pin1 (SENSE1 - ) connect to the ( - ) input for the current comparator.

Pin3 (V

FB) receives the feedback voltage from an external resistive divider (RM5 and CM19)

across the output.

2. Micro-Controller

ICM10 is a 8051 embedded monitor controller (MTV312M64). It plays a major role in the

digital control of the LCD monitor. ICM10 acts as a Key control , DPMS power saving control,

auto-detect controller, and controller of ICM11 to do image processing.

Pin 1 control Inverter enable or disable

Pin 2 enable vcc for panel

Pin3 send a HI signal when audio is invalid

send a LOW signal when audio is valid

pin7 receive HI signal from ICM8 pin6 to reset

pin9,16,26,27,,30,31,32,33 make key function operate when press key button (receive LOW

signal from key button.)

pin13,14 communicate with ICM9(EEPROM) by I

pin17,18,20,21,22,23 communicate with ICM11(scaler) by 6-wire protocol

pin19 detect audio in

pin28 ,29 do ISP(in-system program)

pin34 do mode detect (noramal is LOW , ISP is HI)

Pin 35 control the brightness of panel

Pin36,37 control LED (orange and green) on /off

Pin38 control audio board 12V on/off

Pin40 control Buzzer on/off

Pin41 control ICM3 (regulator)on/off

Pin42 control ICM15,16(LVDS Transmitter) on/off.

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VG800b