akira LCT-27PBSTP, Service Manual

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Model No.: LCT-27PBSTP.doc
Version: 1.0
IC Block Diagram
1. Sound processing IC (MSP3410)
Sound signal send to sound processing N801 MSP3410, and dual-circuit tuner has second
SIF, it sends to N801 (stereo decode and auto volume control), N801 has audio channel
switch, after switching in N581 (HEF4052BT), the audio input of VGA/HDMI/YPbPr will be sent
to N801 together with the audio signal of TV and AV to do the switching process. A way signal
thought volume and high-low sound controlled, output the left and right audio send to digital
audio amplifier N803 (TPA3008) amplify, then it send to speaker, other way signal output
left-right audio send to earphone amplifier N805 (NJW1109), after audio control and power
amplifier, it output to earphone socket. Other two ways signal output audio of TV out and AV
out by SCART terminal of video board. MSP3410 internal block diagram as follow:
Ma
in pins instructions:
2, 3: SCL, SDA 27, 28: left-right audio of audio power amplification 36, 37: left-right audio of
earphone 24, 25: left-right audio of AV OUT 33, 34: left-right audio of TV OUT 47, 48: left-right
audio from main board 50, 51: left-right audio of SCART2 53, 54: left-right audio of SCART1 56,
57: left-right audio of AV IN 67, 69: SIF input of sub-channel and main-channel TV
59: MONO input of sub-channel TV
2. Sub-channel and SCART video signal decode IC (TVP5147)
Sub-tuner TUNER202 decode video, AV, S-VIDEO, SCART1 video, SCART2 video and Y/C
signal, after matching impedance, enter decoding IC N601 (TVP5147), so the PIP image of
sub-channel can selecting arbitrary video signal.