Sanyo NV-E7500 - Navigation System With DVD Player Service Manual page 29

EXPLANATION OF CIRCUIT
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 IC13 .
The audio outputted from DVD BLOCK is outputted to IC13 via GRAND ISOLATOR IC15 .
VIDEO IN AUDIO is switched (input/output) by IC18 and AMP is performed at IC17 and inputted to IC13.
The audio signal outputted from SW is inputted to HEADPHONE SP AMP IC14 with electronic volume,
and volume is adjusted based on the data from the microcomputer and outputted to SPEAKER.
When the power supply SW is turned ON, +5V will be supplied to microcomputer by regulator IC2 .
If the power supply signal from microcomputer is Hi, the IC for DC-DC IC42, IC43 will operate and
+5.1V, +3.4V, and +11V will be outputted.
Furthermore, +8V will be outputted by regulator Q42 .
These power supplies are supplied to block required in each mode.
LCD PCB has POWER SUPPLY BLOCK for LCD and INVERTER BLOCK.
a. POWER SUPPLY BLOCK for LCD
By DC-DC IC IC1001), +14V/-14V power supply for LCD is outputted from +11V supplied from
MAIN PCB, and supplied to LCD PANEL.
b. INVERTER BLOCK
The high pressure for LCD back light is generated based on +11V supplied from MAIN PCB(T1001).
Light adjustment is also performed by DIMOUT signal from microcomputer.
In DVD MODE, the power supply is supplied to DVD BLOCK and SERVO PCB.
The DVD signal from the microcomputer is Hi, and +3.3V and +5V are supplied to DVD BLOCK from
Q2001 and Q2003.
+5V is supplied to SERVO PCB from Q36.
a. DVD DECODER
IC2010 communicates with microcomputer, and playbacks DVD by DVD DECODER.
b. AUDIO DAC
IC2011 outputs DVD audio through BUFFER(IC2013) by DVD AUDIO DAC.
KEY PCB has operation key, LED and SPEAKER output terminal.
DIMMER PCB has remote control sensor port.
DIMMER1 PCB has dimmer sensor port.
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