TDA4780 Datasheet, PDF (13/44 Pages) NXP Semiconductors – RGB video processor with automatic cut-off control and gamma adjust

Philips Semiconductors
RGB video processor with automatic
cut-off control and gamma adjust
Preliminary specification
TDA4780
Table 7 RGB processor mode bits control register
SYMBOL
PARAMETER
CONDITIONS
Control register 1
SC5
sandcastle 5 V
DELOF
BREN
delay of leading edge of
clamping pulse switched off
buffer register enable
NMEN NTSC matrix enable; note 1
Control register 2
HDTV
HDTV / progressive scan for
ADBL line counter
FSBL
full screen black level, e.g. for
optical measurement
BCOF internal black level control off
FSON2
FSDIS1
FSDIS2
FSON1
fast switch 2 on
fast switch 1 disable
fast switch 2 disable
fast switch 1 on
0 = 3-level sandcastle pulse
1 = 2-level sandcastle pulse
0 = delay
1 = no delay
0 = new data are executed just after reception
1 = data is held in a latch (buffer register) and will be transferred to their
destination register within the next vertical blanking interval; the device
does not acknowledge any new data transfer until the internal transfer to
the destination register has been completed
0 = PAL matrix
1 = NTSC matrix; hue position set on −2 degrees
0 = 272 (PAL), 224 (NTSC) lines
1 = 544 (PAL), 448 (NTSC) lines
0 = normal mode
1 = cut-off measurement level during full field, brightness inactive
0 = automatic cut-off control active
1 = RGB outputs clamped to fixed DC levels
see Table 4
Control register 3
ADBL adaptive black
0 = off
1 = on
YHI
Y high level
0 = input = 0.315 V (p-p) (black-white)
1 = input = 1.0 V (p-p) (black-white)
MOD2 modus 2
0 = inactive;
(BCOF = 0) AND (MOD2 = 1) is senseless, no output stabilization
1 = output clamp without brightness adjust, brightness remains active
e.g. for blue stretch
BLST
blue stretch
0 = off
1 = on
YEXH Y exclusive hue
0 = pin 26 is switched to hue adjust output
1 = pin 26 is switched to Y output
RELC relative to cut-off
0 = peak drive limit to absolute output
1 = peak drive limit relative to cut-off
TCPL
time constant peak drive limiter 0 = 2f_H
1 = 1f_H
1997 Feb 06
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