XOCECO LC-27R18, Service Manual

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6
Working principle analysis of the unit
The RF via integrative tuner TUNER1 after, the FBAS is generated. The FBAS, AV1/SVHS(SVHS
priority) and AV2 and so on, its sent N7 (TVP5160) to switch selection and decode. The video is
decoded and generates an AV output. The signal via N7 decode after, it sent 8-bit ITU-R656 format
signal to N10 (FLI2310) non-interlaced processing. It sent 16bit YC signal to main processing
control chip N15(GM1501/1601).
Two ways YPBPR signal via HDTV switch N36(CBT3257C) selection after, it sent RGB switch
N4(CT3257C) and 24bit RGB from pc signal to GM1501/1601.
The HDMI via receiver N34(MST3383MB) processing after, it output VGA signal of 24bit to
GM1501/1601.
They sent to GM1501/1601 picture processing, therein YPBYP or RGB to A/D conversion after, it
and other two signal are switched selection and digital display processing, it include OSD, GAMMA
correction, brightness and contrast processing, then LVDS conversion to LCD panel display.
The SIF of tuner output signal to audio processing NA6(MSP3420),The audio of AV1/SVHS/AV2 via
switch conversion NA3(HEF4052) to MSP3420, the audio of two YPBPR via switch conversion
NA5(HEF4052), the HDMI via MST3383MB decode to audio, it audio via N26(CS4334) D/A
conversion to MSP3420, the audio of VGA sent to MSP3420.
The stereo of the SIF with other four ways audio switch conversion selection to volume control and
audio processing. it output right/left channel audio, one way signal sent SRS processing NA7
(M62494) to SRS sound stereo processing. It via sound amplifier NA9(TPA3008D2) to speaker;
other way signal to earphone and AV OUT R/L output.