B Board; Main Ic Functions; Mc141627Ft (Ic3010), Digital Comb Filter; Upd64082 (Ic3014), 3D Comb Filter - Sony VPL-VW12HT Service Manual

3-2. B Board

This board mainly performs the following processing.
. VIDEO (C-VIDEO, Y/C, 15k-COMPONENT,15k-
RGB), video processing.
. Sync separation processing

3-2-1. Main IC Functions

3-2-1-1. MC141627FT (IC3010), Digital Comb Filter

Performs PAL443, PAL-M, PAL-N 3 line adaptation type
digital Y/C separation.
For the operation clock, the clock (fsc) output from pin 46
of CXA2123 (IC3006) is fed in via pin 45 (IC3010).
The video signal fed in via pin 15 (IC3010) is digitally
processed with this clock.
The resulting Y signal is output from pin 6, and the C
signal from pin 8.

3-2-1-2. uPD64082 (IC3014), 3D Comb Filter

Performs NTSC 3.58 3 dimensional processing digital Y/C
separation.
The reference clock uses the crystal (X3002) connected
between pins 30 & 31, generates fsc and is output from the
FSCO terminal (pin 47). It is then passed through a buffer
into the FSCI terminal (pin 50). As the internal Y-ADC
circuit cannot be used in this IC, the VIDEO signal
subjected to A/D conversion by external A/D converter
uP659AGS (IC3013) to give an 8 bit signal, is fed into pins
74 to 67. The Y signal is output from pin 84 and the C
signal from pin 83.
3-2-1-3. CXA2123 (IC3006), Chroma Decoder &

Sync Processing

This is a chroma decoder/sync processing IC controlled by
2
the I C bus. It can process the C-VIDEO signal and the Y/
C signal.
The C-VIDEO signal is fed into pin 1, the Y signal into pin
44 and the C signal into pin 43.
This allows automatic discrimination between NTSC 3.58,
NTSC 4.43, PAL, PAL-M, PAL-N, SECAM and B/W.
When NTSC 3.58 is discriminated Y/C separation is
performed by IC3014 (uPD64081).
When PAL, PAL-M or PAL-N are discriminated
VPL-VW12HT
IC3010 (MC141627) is driven by a clock and performs Y/
C separation.
They are respectively fed in via pin 5 and pin 7. In the case
of other signals, this IC performs Y/C separation.
When NTSC4.43, SECAM or B/W are discriminated Y/C
separation is performed by IC3006 (CXA2123).
Following this Y/U/V signal conversion is performed with
Y being output from pin 21, U from pin 22 and V from pin
23.
Sync processing is performed by separating H and V from
the input C-VIDEO/Y signal. H-sync is output from pin 9
and V-sync from pin 4.
In the case of 15k-COMPONENT, Y is input from pin 19,
U from pin 18 and V from pin 17. Then Y is output from
pin 21, U from pin 22 and V from pin 23. Sync processing
is performed by separating H and V from the Y signal.
In the case of 15k-RGB, R is input from pin 27, G from pin
26 and B from pin 25. After conversion to Y/U/V, Y is
output from pin 21, U from pin 22 and V from pin 23.
Sync processing is performed by separating H and V from
the C.SYNC signal fed into pin 41.
In each case the H-sync signal output from pin 9 has been
processed by a PLL so the equalizing pulse is removed.
This IC also controls DYNAMIC PICTURE ON/OFF.
3-2-2. Signal Flows
3-2-2-1. VIDEO Signal Flows
The VIDEO, Y/C signals input from CN3001 are fed into
pins 1, 44 and 43 of IC3006.
In the case of PAL, PAL-M, PAL-N and NTSC 3.58, a
signal amplified by a factor of 2 by IC3001 is output from
pin 3.
PAL signals pass though the low pass filter consisting of
Q3022, L3012, L3011, C3086, 3085 and 3084 and are fed
to pin 15 of IC3010 (Comb Filter). Here Y/C separation is
performed with Y being output from pin 6 and C from pin
8. These are passed though the low pass filters consisting
of L3009, C3078, L3010 and C3079 then Y is fed to pin 3
of IC3007 and C is fed to pin 3 of IC3008.
NTSC 3.58 signals pass through low pass filter FL3009
and are fed to pin 4 of A/D converter IC3013.
The digitized signal is fed to 3D comb filter IC3014, then
following Y/C separation Y is output from pin 84 and C
from pin 83. After passing through low pass filters FL3008
and 3007, Y is fed to pin 1 of IC3007 and C to pin 1 of
IC3008.
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