DATA SHEET
VSP 94x2A
If the chrominance signal is below an adjustable
threshold (CKILL (PAL; NTSC) or CKILLS (SECAM))
the color is switched off. To prevent on / off switching, a
hysteresis is given by CON or CONS which is the
value of switching on the color. COLON switches on
the color under any circumstance.
Chroma filter
5
0
5
10
15
20
25
30
35
40
CHRF=’001000’
CHRF=’001100’
The output of the color decoder can be set to UV or
CrCb data by CRCB. For NTSC only, the color impres-
sion (tint) can be adjusted by the Hue Control between
-88° and 90° in steps of 0.7° (HUE). Low chrominance
values (+/- 1...3 LSB) may be deleted by UV-coring
(UVCOR). The Chroma bandwidth can be adjusted by
CHRF. The setting value of CHRF has no linear
impact to the chroma bandwidth. The frequency
response of the Chroma bandfilter are shown in Figure
2-7. Also a filter with asymmetrical characteristic
around the color carrier is available (IFCOMP)
(Figure 2–7). For SECAM mode, the de-emphasis filter
can be adjusted by DEEMPFIR and DEEMPIIR. The
bell filter can be adjusted by BELLFIR and BELLIIR.
CHRF=’001001’
CHRF=’001110’
CHRF=’111001’
0.5
0
1
1.5
2
2.5
3
3.5
4
Frequency (MHz)
Fig. 2–6: Chroma Filter Characteristics
IF Prefilter
10
3.58
4.433
5
0
5
IFCOMP=’100’
IFCOMP=’000’
IFCOMP=’011’
The delay between Y and C is well aligned and can
also be adjusted in steps of 50 ns (YCDEL). No picture
shifting occurs when switching between different color
standards (e.g. SECAM -> PAL). A delay-line is imple-
mented for PAL and SECAM signals. It acts as a sim-
ple chrominance comb-filter for NTSC and can be dis-
abled by COMB. This improves the vertical chroma
resolution, but cross-color remains.
10
15
20
25
30
IFCOMP=’001’
IFCOMP=’010’
0
1
2
3
4
5
6
Frequency (MHz)
Fig. 2–7: IF Prefilter
Micronas
Aug. 16, 2004; 6251-552-1DS
11
MICRONAS [ MICRONAS ]
