EXPLANATION OF CIRCUIT

2.VIDEO BLOCK

a. Microcomputer part

Microcomputer manages the whole set, such as power supply management,

change mode, change image/audio , sensor input processing of remote control or dimmer. Communication with parking brake input and NAVI BLOCK are also performed.

b. Image part

There are 3 kinds of images displayed by this set. NAVI image, DVD image, and VIDEO IN image.

Their signals are switched by VIDEO SW (IC053, IC054) and outputted to LCD

interface IC(IC055).

However, since NAVI image is outputted from NAVI BLOCK and DVD image is outputted from DVD BLOCK by RGB signal, so DVD image and NAVI image are switched by RGB SW(IC051) , and RGB signal of OSD is switched by RGB SW

(IC052), and then they are outputted to LCD interface IC(IC055).

Gamma correction and bright adjustment of the image signal inputted to LCD interface are performed, and then the image signal is out putted to LCD side as RGB signal.

c. Audio part

There are 3 kinds of audio outputted by this set. NAVI GUIDANCE, DVD AUDIO, and VIDEO IN AUDIO.

NAVI GUIDANCE outputted from NAVI BLOCK is directly inputted to SW(IC250). The audio outputted from DVD BLOCK is outputted to IC250 via GRAND

ISOLATOR(IC240).

VIDEO IN AUDIO is switched (input/output)by IC260 and AMP is performed at IC220 and inputted to IC250.

The audio signal outputted from SW is inputted to HEADPHONE SPAMP (IC270)with electronic volume, and volume is adjusted based on the data from the microcomputer and outputted to SPEAKER.

3. POWER SUPPLY BLOCK

When the power supply SW is turned ON, 5V will be supplied to microcomputer by regulator(Q572).

If the power supply signal from microcomputer is “Hi”, the IC for DC - DC(IC110,

140)will operate and 5V, 3V, 3V, 6V, and 14V will be outputted. Furthermore, 8V will be outputted by regulator( Q101).

These power supplies are supplied to block required in each mode.

4.LCD PCB

LCD PCB has POWER SUPPLY BLOCK for LCD and INVERTER BLOCK.

a. POWER SUPPLY BLOCK for LCD

By DC- DC IC(IC601), 16/- 16V power supply for LCD is outputted from

5V supplied from MAIN PCB, and supplied to LCD PANEL.

b. INVERTER BLOCK

The high pressure for LCD back light is generated based on 14v supplied from MAIN PCB. (T431, 432)

Light adjustment is also performed by DIMOUT signal from microcomputer.

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