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Working principle analysis of the unit
1. PAL/SECAM signal flow:
Antenna reception PAL/NTSC/SECAM signal will be send to tuner TAFT-Z711D, t h e n T u n e r
w i l l b e demodulating and output standard video signal TV-CVBS and sound IF signal (SIF).
TV-CVBS will send to the master control IC MST9A881 or MST9B881 to video decode, de-interlace
and scaler, then output LVDS level drive for panel display.
The sound IF (SIF) will be fed into MST9A881 or MST9B881, after demodulating, pre-amplifying,
bass adjusting and volume control, the sound signal will b e t r a n s f o r m i n t o d i g i t a l I 2 S
s i g n a l b y scaler I C and sent to digital amplifier TAS5706 amplifying, then output two ways. One
way will be sent to earphone amplifier TPA6111, another will be sent to speaker.
2. AV/SV signal flow
SV signal and the Video1 path AV signal switch by menu "Setup"->"AV Connecting"->"Video1
input" via terminal socket, the signal and the Video2 path AV signal will be fed to MST9A881 or
MST9B881 to perform video decode, de-interlace and scaler, then output LVDS drive level for panel
display.
Audio signal from AV/SV terminal via matched resistance is fed to MST9A881 or MST9B881 to bass
adjust and volume control, the sound signal will be transform into digital I2S signal by scaler IC and
sent to digital amplifier TAS5706 amplifying, then output two ways. One way will be sent to earphone
amplifier TPA6111, another will be sent to speaker.
3. PC/YPrPb signal flow
PC and the Video3 path YPbPr signal are via terminal sent to MST9A881 or MST9B881 A/D
conversion, output R/G/B of 24 bit to back end module to digital decode, image scale, then send
to LVDS level drive for panel display.
Sound signal of PC/YPrPb t e r m i n a l via matched resistance a n d sent to MST9A881 or
MST9B881 to bass adjust and volume control, the sound signal will be transform into digital I2S signal
by scaler IC and sent to digital amplifier TAS5706 amplifying, then output two ways. One way will be
sent to earphone amplifier TPA6111, another will be sent to speaker.
4. HDMI signal flow
Three HDMI video signals via switcher Sil9185 are directly fed to the master control IC MST9A881
or MST9B881(19" directly into master control IC MST9A881) to digital decode, image scale, then
output LVDS drive level for panel display. HDMI audio signal via decoder built-in MST9A881 or
MST9B881 is fed to back end to bass adjust and volume control, the sound signal will b e transform
into digital I2S signal by scaler IC and sent to digital amplifier TAS5706 amplifying, then output two
ways. One way will be sent to earphone amplifier TPA6111, another will be sent to speaker.
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