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Multimedia ICs
Color TV Signal Encoder
BH7236AF
The BH7236AF converts analog RGB signals into color TV signals in the NTSC and PAL formats. From inputs of
analog RGB signals, a composite synch signal, burst pulses and a color carrier, this IC generates a color TV signal,
and can be adapted for either NTSC or PAL standards, which are selected externally. When set to PAL, chroma
phase is switched for each line.
The chroma signals and luminosity signals can be combined into a color TV signal or output separately, making this
IC suitable for S pins. There are also pins for analog RGB signal output, and each output pin has its own internal
75W driver.
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Applications
TV peripherals
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Features
1) Can be adapted for NTSC and PAL formats.
2) Internal burst timing signal generator with half-H
killer.
3) Internal flip-flop for PAL phase switching.
4) Separate Y / C output pins.
5) Analog RGB signal output pins.
6) Internal 75W driver. (outputs color TV signals, lumi-
nosity signals, chroma signals and analog RGB sig-
nals)
7) Adaptable for color subcarrier pulse input.
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Block diagram
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CLAMP 75W
75W
75W
75W
75W
75W
CLAMP
CLAMP
FILTER PHASE SIFTER
MATRIX
B-Y MOD. R-Y MOD.
F · F
Y / C
MIX
BPF
DELAY
SYNC
MIX
BFP GEN.
BFP
BFP
GND2
ROUT
GOUT
BOUT
VOUT
VCC2
YOUT
COUT
GND1
RIN
GIN
BIN
SCIN
NT / PAL
BFPOUT
SYNCIN
SYNCOUT
VCC1
N. C.
N. C.
N. C.
N. C.
N. C
YTRAP
SYNC
SYNC
SYNC