Service manual

e) Panel Power Sequencing ( VDDCTRL1, 2) ( Pin 32, 3) : The MTV312 has two dedicated outputs

VDDCTRL1 and 2 ( Pin32 and Pin3) to control LCD power sequencing once data and control signals

are stable.

f) Panel interface (Pin 1~25, Pin75~128) : The MTV312 driver interface is highly programmable. It supports

dual bus / dual port for SXGA drivers.

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Pin number Pin Name Pin Number Usage

21 P1.3 Key / Power on ,off

13 P3.4 NV_RAM (U4) SDA

14 P3.5 NV_RAM (U4) SCL

25 P1.7 Key_down

9 P6.3 Key_right

24 P1.6 Key_up

16 P6.2 Key_left

37 P4.1 Key_mute

34 P5.6 VGA connector

23 P1.5 Key_select

42 P5.3 LED_red

41 P5.4 LED_green

32 P6.6 LCD panel power1 on / off control

3 P5.0 LCD panel power2 on / off control

36 P4.0 Backlight on / off control

Power Regulator MC34063A (U6),AIC1739 (Q4) :

The MC34063A is a monolithic control IC containing the primary functions required for DC to DC

internal temperature converters. The device consists of an compensated reference, comparator, controlled duty

cycle. Oscillator with an active current sense circuit. Desired output voltage are determined by the equation,

Volt = 1.25 ( 1 + R67 / R66), In this case, the output voltage are 3.3 Volts

The AIC1739 is a low dropout positive adjustable regulator with minimum of 300mA output current capability.

So it is well suited for 3.3 V and 2.5 V Regulator.

4-7 Power/Inverter Board

This is a specific power/inverter for L7VC monitor 50W 12V 4.16A output power and backlight which

converts 12 Vdc to drive four cold cathode fluorescence tubes.

Inverter Electrical specification described as below

Rated Input Voltage 12Vdc

Input Voltage Range 11.4 ~ 12.6 Vdc

Input Current <2A

Off state Input Power <0.1W

Input

On / Off control Voltage 2~3.3 for on , 0~1 for off

Rated Output Strike-on Voltage 1500Vrms

Rated Output Voltage 710Vrms at 6mA

Rate Output Frequency 40~50KHz

Output

Rated Ourput Current 6~7 mA