Panasonic EURO 4 Chassis Technical Manual page 106

Chapter 3
2.2. Comb Filter Video Processor VPC3215C
The VPC3215C is a high quality, single chip video
front end device providing the following features:
:
Digital video processing
:
High performance adaptive comb filter
:
Multi-standard colour decoder
:
Composite video and S-VHS inputs
2
:
I C bus
:
20.25MHz crystal
2.2.1. Video Signal Processing
To perform video signal processing a number of video
signals are fed from the E-Board to the F-Board via
connector F1 and to the VPC3215C IC1501, where
5 analogue inputs are available for the following video
signals.
:
Pin 58 (Vin4) is fed a composite video signal from
the RCA terminals of AV3 or the luminance signal
of an S-VHS signal input via the 4 pin S-VHS
terminal again of AV3.
:
Pin 60 (Vin3) allows the input of a composite
video signal fed from the scart terminal AV2 pin
20, or in the case of an S-VHS signal input via
AV2 the luminance signal.
CIN
Analogue
VIN1
Frontend
VIN2
VIN3
VIN4
AGC
2*8bit ADC
VOUT
20.25MHz
Clock Gen.
DCO
:
:
:
These video / luminance and chrominance signals are
then fed to the internal analogue frontend which is the
first processing stage of the VPC.
In this first processing stage the signals are fed to an
internal muxtiplexer were the signal or signals are
selected for further processing, before being clamped
and converted to digital by the A/D converters at a
clock rate of 20.25Mhz.
The digital video / luminance signal and chrominance
signals are then output from the A/D converter as 8
bits of digital information, and fed to the Adaptive
comb filter also incorporated in the VPC IC1501.
The 20.25Mhz crystal X1501 which is connected to
the VPC IC1501 at pins 5 and 6 is used to provide all
the necessary clock frequencies required by the VPC
IC1501.
Colour
Adaptive Decoder
Comb
PAL
filter
NTSC
SECAM
VPC3215C
2
I C
23
EURO 4H Supplement
Pin 61 (Vin2) is the input for a composite video
signal input via AV1.
Pin 62 (Vin1) is the composite video signal which
is fed from the tuner stage.
Pin 63 (Cin) allows the input of a chrominance
signal which is input via the scart terminal of AV2
pin 15 or the 4 pin terminal of AV3 when an
S-VHS signal is input.
Horizontal
Scaler
Output
Formatter
Panorama
Mode
Sync. Processing
H/V
3DQDVRQLF
YUV
Clock