Sanyo LC-32U5, Service Manual

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6
Working principle analysis
RF signal from the antenna to tuner, via high frequency amplifier and mix frequency to obtain IF
signal, and then via pre-IF amplifier in V104, then it send to processed IF filter of SAW (Z103),
obtain more idea IF speciality, it processed to IF amplifier, phase locked logic VCO and sync
detection of N101 (M52760E) in the TV board to obtain VIDEO; IF via pre IF amplifier to send to
processed filter of SAW (Z102), again send to processed IF amplifier of N101, decode second SIF.
From M52760E output VIDEO, AV1 and AV2/S signal all send to video decoder N601
(TVP5147PFP), via video select, clamping, A/D transfer, comb filter and color decode, one way
output AV OUT, another way output 8bit for CIR656 format signal and CLK signal, send to
N101(MST6151) of CPU board, Also YPbPr, VGA and HDMI send to N101. N101(MST6151) is
many function big dimension integrate circuit, it processed HDMI, A/D to D/A switch, interlaced and
non-interlaced processing, model switch and low voltage difference output functions and so on, it
send to four ways difference signal and one way clock signal to LCD display.
From HDMI input to MST6151contain sound signal, via processed MST6151, send to processed
D/A switch for NA01(CS4340), output L/R of HDMI.
L/R of HDMI from CS4340 output, L/R of YPbPr and VGA/DVI signal via sound switch
NA02(HEF4052) to select, then send to sound processing N801(MSP3425G); L/R signal for AV1
and AV2/S input send to N801 via selected switch N701(HEF4052),and SIF of TV output from
M52760E send to N801 too. In MSP3425G, the demodulated L/R of SIF and the input L/R from
other two ways, via selected switch and processing sound, then output signal, one way sound
output for AV OUT, other way send to N401(TPA3008D2) of sound amplifier, via amplify for sound
signal to speaker and earphone.
The unit working is controlled N801(MTV412) of CPU, connect tuner, TVP5147 and MSP3425G to
IIC bus; connect MST6151 to parallel BUS.
Item Setting Item Setting Item Setting
Picture mode NATURE OSD language English CCD OFF
Sound mode NORMAL HALFTONE 50 STEREO ON
N/R WEAK DURATION 30 VGA/HDMI NORMAL
SCREEN FULL MAG.C ON ANTENNA CATV