Working Principle Analysis Of The Unit - Sanyo AVL262 Service Manual

Working principle analysis of the unit

The RF signal received by antenna will be sent to tuner TUNER601, then IF signal will be
obtained through high amplified, mixed frequency. After pre-intermediate amplified by V602, it will
be sent to acoustic surface-wave Z602 to do IF filter and get better IF characteristics, then it will be
sent to N602 (R2S40401) to do intermediate amplification, phase-lock loop VCO and synchronous
wave detection to get the composite video signal TV-CVBS; after pre-intermediate amplification IF
will also be sent to acoustic surface-wave Z601 to do filter at the same time, the it will be sent to
N602 to do intermediate amplification and output the second sound intermediate frequency signal
TV-SIF.
The TV-CVBS and TV-SIF signal will be sent to main IC N304 (MST9U89). Video signal of AV1,
AV2, S-VIDEO, YPbPr1 and YPbPr2 will also be sent to MST9U89, their audio signal via audio
switch N207 (HEF4052BT) selection to MST9U89 (AV1 and S-VIDEO share the same audio jacks).
HDMI1, HDMI2 and HDMI3 via HDMI switch N504 (TMDS351) selection, then sent to MST9U89
together with VGA.
The main IC N304(MST9U89) is a high performance and fully integrated IC, which can realize
HDMI interface processing, video decoding, video switch selection, A/D and D/A conversion,
interlace/de-interlace processing, modes conversion, OSD and low-voltage differential output, ect.
And it also has functions of audio selection, processing and MCU.
The video signal via MST9U89 processing, output 4 pairs differential signal and 1 pair clock
signal for LCD panel display.
The audio signal via MST9U89 processing, it will be sent to N206 (BH3547F) amplifying to
earphone. The audio signal will also sent to sound amplifier N203 (TPA3120) amplifying to speaker.
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