Sanyo DP46142, Service Manual

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3. Working principle analysis of the unit
1. NTSC signals flow:
Antenna signal will be send to tuner ENV56U05D8F, t h e n T u n e r wil l b e demodulating and
output standard video signal TV-CVBS, and sound SIF signal.
TV-CVBS will send to the master control IC ZR39748 to video decode, de-interlace and scaler, then
output LVDS level drive for panel display.
The sound IF (SIF) will be fed into ZR39748, after demodulating, pre-amplifying, bass adjusting and
volume control, the sound signal will be tra nsf orm into dig it a l I2S s ig na l and sent to
digital amplifier TAS5707L.
2. Composite/Component signal flow
Composite signal and Component signal will be fed to ZR39748 to perform video decode, de-
interlace and scaler, then output LVDS drive level for panel display.
Audio signal from Composite/Component terminal via matched resistance is fed to ZR39748 to bass
adjust and volume control, the sound signal will b e transf orm int o d ig ita l I2 S s ig nal and sent
to digital amplifier TAS5707L.
3. HDMI signal flow
Two HDMI video signals are directly fed to the master control IC ZR39748 to digital decode, image
scale, then output LVDS drive level for panel display. HDMI audio signal via decoder built-in ZR39748
to bass adjust and volume control, the sound signal will be tra nsf orm into d ig ita l I2 S s ig na l
and sent to digital amplifier TAS5707L.
4. USB signal flow
USB signal via USB connector sent to ZR39748 and its A/D conversion to YPbPr output for
ZR39748, then output R/G/B of 24 bit to back end module to Video decode, de-interlace and
image scale, then send to LVDS level drive for panel display.
Sound signal of USB signal v i a matched resistance a n d sent to ZR39748 to bass adjust and
volume control, the sound signal will be tr ansf orm into d ig ita l I2S sig na l and sent to digital
amplifier TAS5707L.