25
the AV/S and IF signal which is demodulated by main demodulator are sent by TV plank into video
decode chassis UOC for decoding ,then the output analog video signal is sent into analog
Ⅲ
-to-digital
converter TDA8759HV/8/C1 for A/D transform to produce R
、
G
、
B digital signals which are transformed in
format by GM1601/GM1501, then, it transformed the different input formats into the uniform up-screen
signal format.
The signal demodulated by sub demodulator is directly sent into submenu video decoder
SAA7115HL/V1 for video decoding and A/D conversion
，
then again sent into GM1601/GM1501 to do
format transform, the output up-screen is used for submenu display.
After selection, the PC
、
HDTV(YPBPR) and DVI signals are sent directly into GM1601/GM1501 for
processing to form uniform up-screen signal.
2.
Accompanying sound flow:
TV
accompanying sound
：
RF signal is demodulated by main demodulator to SIF(companying
sound intermediate frequency) signal, SIF is sent into UOC for demodulation and sound dis
Ⅲ
posal
，
then,
the output audio signal is zoomed in by D class TPA3002D2PHPR and is sent into the speaker at last.
AV
companying sound
：
the audio signal input by AV is directly disposed by UOC and zoomed in
Ⅲ
by TPA3002D2PHPR,then transported to the speaker.
After the
companying sound of
PC
、
DVI
、
YPbPr are selected by MC74LVX4052DR2 , then they are
disposed by UOC and zoomed in by
Ⅲ
TPA3002D2PHPR to make the speaker work.
3.
、
TV power supply system
：
4 channels voltage are transported from the power supply board, they are +24V
，
+12V
，
+5V and
+5VS. +24V is provided for inverter of LCD panel, +12V is provided for PA, +5V is transformed by the
manostat into 3.3V
、
2.5V and 1.8V for IC, it may be turned down under standby mode, while +5VS is
provided for MCU
、
infrared receiver
、
EEPROM.
5V is divided into two ways, one way is provided for other IC and apparatus, the 5V will be turned
down under standby mode, but can not be cut off.. The other 5V is provided for MCU
、
infrared receiver
、
EEPROM and so on, it would not be cut off under standby mode.
