XOCECO PH-50FB31, Руководство по обслуживанию

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Working principle
1. PAL-BG signal flow:
Antenna reception PAL-BG signal send to the integrative tuner FQD1216, which contains HF and IF
amplifier circuit and video decoding circuit. It is controlled by main IC ZR39660 (inside CPU)
through I2C bus. The PAL-BG signal via frequency tuning, HF amplification, IF amplification, system
switching and decoding, output video signal TV-CVBS of 1Vpp and sound IF signal (SIF).
TV-CVBS and AV1-CVBS, AV2-CVBS input from AV terminal, via switch IC HEF4052 to output
signal, one way send to ZR39660 for VEDIO DECODER, DEINTERLACE and SCALER, then send
to LVDS level drive for LCD screen, another way is output through AV output socket as AV OUT.
The sound IF (SIF) is fed into demodulation IC SGTV5810, via demodulate, pre-amplify, woof adjust
and volume control, output left/right sound signal to digital audio amplifier TPA3001 amplify, then
send to speaker.
2. DVB-T signal flow:
Antenna reception DVB-T signal send to tuner FQD1216, after frequency tuning, HF amplification,
IF amplification and SAW FILTER, output IF signal to demodulation chip DRX3975, via QAM
demodulation, fed to ZR39660 for information source decoding in the format of standard serial TS
stream.
HD video signal via decoding to A/D conversion and OSD superposition, at last send to LVDS drive
level for PDP panel.
HD audio signal, via decoder built-in ZR39660, resumed to multi- channel sound of Dolby AC-3, at
the same time output data stream of I2S format and S/PDIF data stream. Audio data of I2S format is
fed to audio D/A conversion chip CS4345 to output analog L/R signal. S/PDIF data stream directly
output from optical fiber interface.
3. PC/YPrPb signal flow
PC and two YPBPR signal via matched resistance, it a-c couple to Triple Video A/D Converter
TDA8759 A/D conversion. Send B/G/B of 24 bit to main IC ZR39660 digital decode, image scale
and OSD superposition, then send to LVDS level drive for LCD screen.
Sound signal (PC, YPrPb) via matched resistance and a-c couple, it send to SGTV5810 (sound
processing and volume control) switch of audio. Select right/left sound channel, their send to digital
sound amplifier TPA3001 amplify, then send to speaker.
4. HDMI signal flow
HDMI video signal is directly fed to main IC ZR39660 (with HDCP function of HDMI) digital decode,
image scale and OSD superposition, then output LVDS drive level for screen.
HDMI audio signal, via decoder built-in ZR39660,output data stream of I2S format and S/PDIF data
stream at the same time. Audio data of I2S format is fed to audio D/A conversion chip CS4344 to
output analog L/R signal. S/PDIF data stream directly output from optical fiber interface.