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-37-

RF Signal Input

(NTSC)

I

2

S

I

2

S

SIF

IEC958

IC401

DTV Controller

IC602

Audio Processor

IC603

OP Amp.

Speaker

Stereo(L/R)

IC708

Digital Audio Amp.

P501

SPDIF Output

Connector

P706, P707

Audio Output

Connector

IC105

TUNER

The audio signal of the analog RF signal(NTSC) received in the input terminal of the tuner(IC105) is sent out as the
sound IF signal by the tuner.
The SIF signal goes through Automatic Volume Correction(AVC) in the audio processor and sent to the 
OP Amp(IC603).
This signal is amplified to be sent to the audio processor again.
The audio processor converts the stereo signal into I

2

S format to send to DTV controller and PCM data is outputted

in I

2

S format through audio decoding process.

This signal is converted to the stereo signal(L/R) in the digital audio amp(IC708) to be sent to the internal speaker
through the audio output connector(P706, P707).
Also the digital audio data in IC401 outputs the PCM data in SPDIF format through P501.

-38-

AV1, AV3 Input

AV2 Input

LCD Panel

CVBS

CVBS
for Caption

I

2

C Comm.

CVBS

LVDS Signal

P703

RCA Jack

CN105

Wafer

IC706

Analog MUX

(Video switch)

IC401

DTV Controller

IC107

SD Video Filter

IC705

Micro Processor

P503

LVDS Connector

External input AV1 and AV3 are received through the RCA jack of P703, and AV2 is received through the 6 pin
wafer of CN105.
These signals all come to the analog video switch(IC706) and only 1 signal is selected. In other words, it is the same
as the analog RF signal.
The one signal that has been selected for output is decoded in the DTV controller and converted to LVDS signal to
be sent to the LCD panel through the LVSD connector(P503).
Also the output signal from the analog video switch is used for caption.
The signal received from IC107 is filtered and amplified 2 times to be received by the microprocessor.
The microprocessor analyzes(caption slicing) this signal to send the caption information.

-39-

AV1, AV3

(S-Video) Input

AV2 Input

I

2

S

I

2

S

IEC958

IC401

DTV Controller

IC602

Audio Processor

IC601

Audio Switch

Speaker

Stereo(L/R)

IC708

Digital Audio Amp.

P501

SPDIF Output

Connector

P706, P707

Audio Output

Connector

CN105

Wafer

P703

RCA Jack

The left/right audio signal of AV1, AV2 and AV3(S-Video) is received by P703 and CN105, and the AV3 uses the
same audio terminal as S-Video.
One stereo signal among the signals received through the audio switch(IC601) to send to the audio process(IC602).
The Audio switch receives the audio input signal of AV1, AV2, AV3(S-Video) and component1, component2,
PC(DVI) to select and output one stereo signal.
The stereo signal selected this way is converted to I

2

S format in the audio processor to send to DTV controller for

output I

2

S format through audio decoding process.

This signal is converted to stereo signal (L/R) in the digital audio amp(IC708) to send to the internal speaker through
audio output connector(P706, P707).
Also the digital audio data in IC401 is outputted as PCM data in SPDIF format through P501.

-40-

S-Video Input

LCD Panel

S-Video

CVBS
for Caption

I

2

C Comm.

LVDS Signal

IC706

Analog MUX

(Video switch)

IC401

DTV Controller

IC107

SD Video Filter

IC705

Micro Processor

P503

LVDS Connector

P101

S-Video Jack

S-Video signal is received through P101 jack.
Y signal and C signal are separated in this signal and is received directly by DTV controller(IC401) and decoded by
IC401 to convert to LVDS signal.
Then it is sent to the LCD panel through P503.
And the caption signal is send to IC401 through the video filter (IC107) and microprocessor(IC705) via analog video
switch(IC706).
The audio signal of S-Video is used as the audio signal of AV3.