Copyright©2007 LG Electronics. Inc. All right reserved.
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LGE Internal Use Only
Only for training and service purposes
4. Analog RF(NTSC) Audio signal flow chart
*Tuner(NTSC) Audio signal flowchart
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.