Philips DPTV465 Service Manual page 91

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Circuit Descriptions, List of Abbreviations, and IC Data Sheets
The circuit located on the SSB labelled the Feature Box
performs the digitising, line doubling, and picture resizing. The
main functions are performed by 7611, PICNIC (PICture
improvement Network IC), and 7718, FALCONIC (Field And
Line Converter and Noise reduction IC). The PICNIC IC
performs the A/D Analogue-to-Digital conversion while the
FALCONIC performs the Line Doubling. The FALCONIC also
performs the Super Zoom, Panoramic, 4:3, Movie Expand
14:9, Movie Expand 16:9, 16:9 Subtitle, and Widescreen
picture format conversions.
The YUV signal is fed to the PICNIC on Pins 23, 25, and 26.
Horizontal and Vertical Sync is fed to the IC on Pins 28 and 29.
The signals are fed to a Clamping circuit to limit the sampling
range, an AGC, and a Prefilter circuit. It is then fed to a triple A/
D converter, Time Base Corrector, Noise Reduction and
Histogram circuit, and a Multiplexer. The Prefilter circuit limits
the bandwidth of the signals to prevent aliasing. Aliasing shows
up as artefacts in the picture, which is caused by under
sampling. The Multiplexer combines the three data streams.
Data is output from the PICNIC to FM1 (Field Memory), IC
7714. The Fields are ready by 7718 to the Dynamic Noise
Reduction circuit and to the processor. The De-Interlace writes
the Field data to Field Memory 2, 7717 and Field Memory 2,
7719. The Processor then reads the Field memories to convert
the signal to a progressive scan signal. A Motion Estimator
processes moving blocks in the picture to produce a natural
motion. The processors resize the picture to fit the format
selected by the user. However the picture appears to be
formatted, the output is always a 480P or 576P format. The
Signal is output on two 16-bit busses, F and G, to the Eagle
processor.
The FALCONIC is controlled by the microprocessor in the
PICNIC. The PICNIC is controlled by the Fast clock and data
line from the OTC. The PICNIC communicates with the
FALCONIC and the Eagle via the SN clock and data line. This
is called a SNERT interface. SNERT is a No parity Eight-bit
Reception and Transmission interface.
Horizontal and Vertical sync is output on Pins 18 and 19.
9.3.13 Eagle
7722
16b
F
FM4
VERT
INPUT
HORIZ
MUX
PEAK
16b
7723
G
FM5
SN_CL
SNERT
CONTROLS
INERFACE
SN_DA
Figure 9-20 Eagle
The Eagle circuit provides Skin tone correction, Blue stretch,
and Green Enhancement. In versions, equipped with the Pixel
Plus feature, the Eagle IC performs the corrections for this
mode.
The video frames are sent to FM4 and FM5, 7722 and 7723,
memories from the FALCONIC IC. These memory ICs hold the
frame data until they are required for processing by the Eagle.
The Input Multiplexer selects which frame is to be read. The
Vertical and Horizontal Peaking circuit sharpens the edges and
adds blue pixels to enhance the picture. This circuit is part of
the Pixel Plus processing.
The Scaling circuit scales the picture to a 100 Hz Digital Scan,
75 Hz Digital Scan, 576 progressive, or 480p progressive. If the
input signal is from an NTSC source, only 75 Hz or 480p is
7731 7728
54
Y_EAGLE_E
D/A
7732
7729
63
YUV
SCALING
U_EAGLE_E
FORMAT
7733
7730
73
V_EAGLE_E
28
7724
HD_E
EAGLE
SYNC
29
VD_E
E_15000_085.eps
available. The signal is converted to an analogue format and
output on Pins 54, 63, and 73. Sync is output on Pins 28 and
29. The signal is then fed to a buffer circuit on the SSM and
then to the HOP. The Eagle is controlled by the microprocessor
in the PICNIC IC via the SNERT interface. The Eagle outputs
an analogue YUV signal to the SSM (Small Signal Module).
9.3.14 SSM HOP Buffer Amplifiers
The Y-SSB, U-SSB, and V-SSB signals are fed to buffer
amplifiers, located on the SSM. Transistors 7806 and 7807
buffer the Y signal. The U signal is buffered and inverted by
transistors 7810 and 7811. The V signal is buffered and
inverted by transistors 7808 and 7809. The YUV signal is then
fed to the HOP panel via connector 1250.
9.3.15 HOP RGB/YUV Switching
181004
Figure 9-22 RGB/YUV switching
The input to the HOP panel can be RGB or YPbPr via the cinch
connectors or the Sub-D connector. This connector is not
present in the Basic or Basic Plus versions. The RGB or YPbPr
signal can be either 480P progressive scan or 1080i interlaced.
IC 7110 selects between the R/Pr-G/Y-B/Pb and the RGB
signal from the Sub-D connector. The output of 7110 is fed to
7210, which selects between the output of 7110 and the YUV
signal from the SSM.
DPTV465
E_15000_086.eps
181004
Figure 9-21 SSM YUV-buffers
9.
EN 91
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181004

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