Zenith C32V23 - 32" Flat-Screen Integrated HDTV, Руководство по обслуживанию

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PV154 - 923-03497
3-7
AB - SERVICING
SERVICING
SMALL SIGNAL MODULE
The AB chassis features 10 IC's for small signal processing
and 5 regulators for small signal power supply. The
ICM2200 CXA2150Q (0IMCRSO007A) is the video and
synchrony selector and ICM2700 is the video driver.
They work together to process all video signals and
synchrony (see the block diagram), this circuit is the
heart of AB chassis. The main board employs one
additional daughter board that processes the digital
signal for HDTV reception. This board is shielded and is
connected through CNP200A and CNP201A.
Y in
Cb in
Cr in
H in
V in
BW DRV
H DRV
HC PARA
V DRV-
V DRV+
VTIM
B-OSD
G-OSD
R-OSD
FB-OSD
HT-OSD
SVM_OUT
VPROT
HP-IN
ABL-IN
R-OUT
G-OUT
B-OUT
IK-IN
B-PIP
G-PIP
R-PIP
FB-PIP
Video
Processing
CXA2150Q
SVM module
LARGE
SIGNAL module
VIDEO
OUTPUT module
PIP Processor
“provision”
Video/Sync Selector
CXA2151Q
LARGE SIGNAL module
Micro processor
Y aw
Cb aw
Cr aw
H sync sw
V sync sw
SD A-1, SCL-1
SIF (from Tuner)
SIF (from 2ndTuner)
“Provision”
SIF-1
SIF-2
AUX-L/AUX-R
from Switcher
ADC
DE-
MOD
Pre-
proc
DAC
H/P
DAC
DAC
DAC
ADC
Pre-
scale
Pre-
scale
SCART
DSP
Input
Select
SOUND
PROCESSOR
MSP4450G
So
ur
c
e
Se
le
c
t
SDA-1, SCL-1
Audio Amp
TDA 7263
R Audio out
SCART
Output
Select
Monitor out
L monitor
R monitor
12S_CL
12S_WS
12S_DA_OUT
Analog Main BD
Power Mute from
Microprocessor
L Audio out
AUDIO SYSTEM
The AB chassis is offers up to five audio input sources
and an AUX output for MONITOR through the RF Switch.
The tuner delivers IF signals that are processed by U1200
and U1201 saw filters. Finally the IF signal is applied to
IC1203 which contains IF amplifiers and AGC circuits.
AGC adjustment is manually done through R1242. This
IC also delivers the down converter digital IF signal to
the digital board which is connected to CNP200A and
CNP201A connectors. The it processes the audio and
video signals and the audio is delivered to IC1400.
The IC1400 MSP44506 (0IMCRMN012A) is the audio
processor. It handles the ANALOG IF and decodes the
analog stereo signal and includes audio tone controls.
The EZBASS circuit is for BASS and TREBLE enhancement.
The following is the block diagram for this IC and the
audio system.