Sony KP 48S70, Руководство по обучению

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11
Picture and Picture (V Models)
Overview
The V model RA-3 chassis has features for PIP and P & P. The P & P
feature is also unknown as Twin View. Since this unit has the P & P
feature, the signals from both the main picture path and the sub picture
path are input to the P & P controller. The output from the P & P controller
can be used for Twin View or normal PIP.
Main Y Signals
The Main Y signal from IC1410/7 is split to four places. They are:
ƒ
IC1407/19 YUV Controller TV IN for main picture.
ƒ
Q1406 Sync separator to IC1402 Main Decoder for decoder sync.
ƒ
IC1402/34 Main Decoder Y In for P & P.
ƒ
IC1404 YUV Switch for when a component input is selected as the
main picture
Main C Signal
The Main C signal is input to IC1402/32. This signal will be used along
with the Y signal to create component video signals.
Main Decoder and YUV Switch
IC1402 Main Decoder decodes the Y and C signals. The decoded sig-
nals YUV are output from IC1402/18, 19 and 20 respectively.
These signals are then input to IC1404/2, 12 and 5. IC1402 has another
set of YUV signals input at pins 1, 13 and 3. These signals are the Main
Y signal. The U and V signals come from CN401/1 and 3. This connector
is connected to the U board and couples the MUV and SUV signals from
the Video 4 and Video 5 component inputs. IC1404/9, 10 and 11 are
connected to IC1409/4 DVD SW. IC1409 is a D/A Converter that outputs
either a High or a Low depending on which composite/S video input or
component input is used for the main picture. The selected YUV signals
are output at IC1404/15, 14 and 4. These signals are input back into
IC1402 Main Decoder at pins 11, 12 and 13. These signals are passed
through an auto pedestal adjusting circuit and output at IC1402/8, 7 and
6. These signals are then sent to IC1405 P & P Controller.
Picture and Picture Controller
The main picture YUV is input to IC1405/10, 6 and 8. The Sub picture
signals goes through a similar decoder and YUV Switch and are input to
IC1405/71, 75 and 73.
IC1405 is a picture-and-picture controller. It contains ADCs, reduction
circuitry, memory control, display control and DACs. It is capable of show-
ing two pictures of equal size side by side or free position PIP.
The built-in memory controller of IC1405 P & P Controller is used to oper-
ate IC1401 V RAM. This 2 Meg of V RAM is used to produce the child or
Twin View pictures. IC1405/40 SC is used to clock the data into the RAM.
This signal looks similar to the DFB signal, which changes according to
the window size selected. IC1405/31 DT is the data transfer output to the
V RAM. IC1405/47 is the write enable line. IC1405/48 and 49 are the
CAS and RAS lines used to refresh the memory.
IC1405/86, 90 and 88 are the respective YUV outputs for PIP & P and P.
These signals look like component video, but are reduced in time. This
means that they do not use the full 1/60
th
of a second that would be used
by a normal signal. The time that the signal appears is relative to the size
of the PIP window. IC1405/93 DFB is the signal that will be used to deter-
mine the size and position of the PIP window. One of the waveforms
below shows what the DFB signal looks like when P & P is selected. The
other shows the DFB signal when a 1/9 PIP window is selected.