Sony TVP-08 Training Manual page 55

IC1306 3D Comb Filter
The data from IC1309 ADC is input to IC1306/67-74 DYC02 – DYC09.
The DYC00 – 01 inputs are grounded through resistors. Timing is set up
for these inputs by IC1306/76 CSI, the composite sync input, and also by
IC1306/50 FSCI. The input at IC1306/76 is the composite sync input
from the main Y buffer and it controls the timing generator inside of IC1306
3D Comb Filter. IC1306/50 FSCI receives a 3.58 MHz signal, which origi-
nates at IC1305/30. This signal controls the system clock internal to IC1306
3D Comb Filter.
Once the data from the digitized video signal is received by IC1306 3D
Comb Filter, it is read into IC1306' internal EDO memory controller. The
EDO control reads and writes data into and out of IC1304 Frame Memory
and also controls the addressing, write enable and refreshing of the frame
memory. Data is read in and out between IC1306/13-28 and IC1304/2-5,
7-10, 39-36 and 34-31. Addressing is done between IC1306/9-2 and 99
and IC1304/16-19 and 26-22. The write enable signal is sent from IC1306/
1 MWE to IC1304/13 WE. This allows the memory controller inside IC1306
to write data to the locations addressed while WE is LOW. IC1306/12
MOE is the output enable line that allows IC1304 Frame Memory to have
data read from it by IC1306 3D Comb Filter. This line is connected to
IC1304/27 OE.
IC1304 Frame Memory is four Megs of EDO memory. Since IC1304 Frame
Memory is EDO type memory, it needs to be refreshed constantly. This is
done using the RAS (Row Address Strobe) and CAS (Column Address
Strobe) lines. IC1306/10 MCAS outputs a CAS signal to IC1304/28 and
29 UCAS and LCAS. IC1306/98 MRAS is output to IC1304/14 RAS. These
lines keep the memory constantly refreshed and are always active.
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The comb filter uses the memory controller for three different purposes.
The first is to feed signals that are line delayed by 1H and 2H into the line
(2D) comb filter. The second is to feed signals that are line delayed by 1H
and 526 H into the frame (3D) comb filter. The third section is the motion
detector block that looks at all of the signals and determines if there is
motion or not. This circuit is connected to a mixer that outputs either the
output from the line comb filter if there is motion, or the output from the
frame comb filter if no motion is detected.
After the filtering is complete, the separate Y and C components are input
to noise reduction circuits. Noise is subtracted out of the signals and then
they are ready to be output. Y is output from IC1306/84 AYO to Q1354/B,
which is part of a buffer circuit. The C signal is output from IC1306/83
ACO to Q1358, which is part of a buffer.