Sony RM-PJM50, Руководство пользователя

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4-1
VPL-FX50
Section 4
Descriptions of Circuit Board Operations
4-1. QB Board
This board mainly performs the following 3 processes.
.
Communication with the CPU by RS232C.
.
Reception of the Remote Control Signal (SIRCS).
.
Input of the Video Signals.
4-1-1. Communication with CPU through
RS232C
IC2100 is used as a communication buffer. It is connect-
ed through the CN2102 to the computer while the signal
flows in the order of IC2100
→
CN2101
→
BB board
→
C board and performs communication with the CPU in
the C board.
4-1-2. Reception of Remote Control
Signals (SIRCS).
Signals from the Remote Control connected by the cable
are input through the J2102. Then, it is reversed by the
Q2103 and output to the BB board from the CN2101 (6)
pin.
In case the J2102 not connected by the cable, the signal
received by the QA and N board is input from the
CN2101 (7) pin, goes back to the CN2101 through the
J2102 again and output to the C board from the CN2101
(6) pin.
4-1-3. Input of the Video Signal
The Video signal is input from J2101 and output to the
BB board from the CN2100.
4-2. BA Board
This board mainly performs the following processes.
• Video Input Process of Video (C-Video, Y/C)
• Sync Separation
4-2-1. Functions of the main ICs
4-2-1-1. CXA2123 (IC4000), Chroma decoder &
Sync processes
CXA2123(IC4000) is IC to perform Chroma decoder /
Sync processes controlled by the I2C Bus Control. It
processes the C-Video and Y/C signals.
CXA2123(IC4000) automatically controls NTSC3.58,
NTSC4.43, PAL, PAL-M, PAL-N, SECAM and B/W
while C-Video, Y and C signal are input to the
1
pin,
$]
pin and
$[
pin ,respectively.
This IC performs Y/C separation except NTSC3.58 and
PAL. These signals are converted to Y/U/V signal and
output as (Y), (Cb ) and (Cr) from
@-
pin,
@=
pin, and
@[
pin respectively.
While C-Video / Y signal are separated into H and V, H-
SYNC and V-SYNC respectively is output from the
9
pin and
4
pin in the Sync processes.
4-2-1-2. UPD64882 (IC4007), 3D Digital • Comb
Filter
This is IC of the 3D Digital Comb Filter controlled by the
I2C Bus. It performs Y/C separation for NTSC3.58.
C-Video is input to the
*,
pin, converted to digital by
internal 10bits A/D converter, then Y/C separated accord-
ing to the signals of sorts of circuit when Y signal from the
*]
pin and C signal from the
*[
pin is output.
IC4006 is an extended 4M bits Field Memory of IC4007. It
generates the Frame-delay (525H) and Field-delay (262H)
signal.
4-2-1-3. MC141627FT (IC4005), 3 line. Comb Filter
This is IC for Y/C separation of PAL.
C-VIDEO signal is input to the
!\
pin, converted to digital
by internal 8bit A/D converter and then Y/C separated. Y,
and C signal is respectively output from
6
, and
8
pin.
4-2-2. Flow of Signal
4-2-2-1. C-VIDEO
C-VIDEO signals from the CN4000 (A6), and (B6) pin are
input to IC4000
1
pin, multiplied by 2 and output from
the
3
pin of IC4000.
In case of PAL, C-Video is input to IC4005
!\
pin through
a buffer circuit which is composed of Q4006 etc., and then
Y/C separated. Y and C signal respectively output from
IC4005
6
pin and
8
pin. Each Y and C signal passes the
Low Pass Filter and is input to the switch IC4002
3
pin
for (Y) and to IC4003
3
pin for (c).
As regards NTSC3.58, C-VIDEO is input to IC4007
&'
pin through a buffer circuit which is composed of Q4022
etc., and then Y / C separated.
After this process, Y signal is output from IC4007
*[
pin
while C signal is from the
*[
pin. Each Y, and C signal
passes through the Low Pass Filter, and then is input to
IC4002
1
pin and IC4003
1
pin, respectively.