7-2
1. Power Supply (Circuit Diagram: Power PWB)
1.1 I322: DC-DC Converter
A 5V power supply for LCD module, CPU, and logic is generated from the 19V source.
1.2 I323: 3-terminal Regulator
A 3.3V power supply for Scaler IC I315, LVDS IC I319, I320 is generated from the 5V source.
1.3 I330: 3-terminal Regulator
A 3.3V power supply for SDRAM IC I316, I317, I318 is generated from the 5V source.
1.4 I324: 3-terminal Regulator
A 2.5V power supply for Scaler IC I315 is generated from the 5V source.
Q307, I321 ON/OFF control for LCD module.
ON/OFF control is performed for power ON/OFF and also for the power saving sequence.
2. Video Input Circuit (Circuit Diagram: Interface PWB)
The analog video signal input to I/F board from P304, the AC-coupled video signal is used to clamp the
block level at 0V.
The digital video signal (TMDS) input to I/F board from P303.
3. Definition Converter LSI Peripheral Circuit (Circuit Diagram: Interface PWB)
I315 gm5020 is the definition converter LSI.
The analog R,G,B signal input entered from the video input circuit is converted into the digital data of video
signal through the incorporated A/D converter. Based on this conversion, this device performs interpolation
during pixel extension. The source voltage for this device is 3.3V, 2.5V and the system clock frequency is
24MHz. The withstand voltage level for the input signal voltage is 3.3V and 5V.
4. System Reset, LED Control Circuit (Circuit Diagram: Interface PWB)
4.1 System Reset
System reset is performed by detecting the rising and falling of the 5V source voltage at I301.
4.2 LED Control Circuit
LED Green / Amber color is controlled with signal from I302 pins 25 and 26.
(Circuit Diagram: Interface PWB).