TDA4687 Philips Semiconductors, TDA4687 Datasheet - Page 17

• Manufacturer Part Number: TDA4687
• Description: Video processor with automatic cut-off control
• Manufacturer: Philips Semiconductors

Philips Semiconductors
Table 3 Demodulator axes and amplification factors
Table 4 PAL/SECAM and NTSC matrix; note 1
Note
1. PAL/SECAM signals are matrixed by the equation: V
1997 Jun 23
(B
(R
(R
(B
handbook, full pagewidth
Video processor with automatic cut-off control
(1) Maximum brightness.
NTSC signals are matrixed by the equations (hue phase shift of 5 degrees):
V
In the matrix equations: V
the NTSC demodulator. V
to the demodulator axes and amplification factors shown in Table 3. V
R
Y)* demodulator axis
Y)* demodulator axis
Y)* amplification factor
Y)* amplification factor
Y*
= 1.57V
cut-off measurement line
R Y
for red signal
PARAMETER
PAL/SECAM
MATRIX
0.41V
NTSC
(2) Nominal brightness.
G
R
B Y
Y
Y*
and V
, V
; V
R
G
Y*
B
Y*
Fig.6 Cut-off measurement pulse.
and V
Y
= 0.43V
are conventional PAL demodulation axes and amplitudes at the output of
B
Y*
R
are the NTSC modified colour difference signals; this is equivalent
Y
G
17
0.11V
Y
= 0.51V
B
(1)
(2)
Y
; V
R Y
NTSC
115
1.97
2.03
B
0
G
Y*
Y*
0.19V
= V
= 0.27V
B
B
Y
NMEN
Y
0
1
R
Y*
ultra-black
0.22V
MHA697
Product specification
PAL
1.14
2.03
B
TDA4687
90
0
Y*
.