Philips Semiconductors
Product specification
9-bit video input processor
SAA7113H
The high frequency components of the luminance signal
can be peaked (control for sharpness improvement via
I2C-bus subaddress 09H, see Table 36) in two band-pass
filters with selectable transfer characteristic. This signal is
then added to the original (unpeaked) signal. For the
resulting frequency characteristics see Figs 11 to 18.
A switchable amplifier achieves common DC amplification,
because the DC gains are different in both chrominance
trap modes. The improved luminance signal is fed to the
BCS control located in the chrominance processing block,
see Fig.19.
8.4
Luminance processing
The 9-bit luminance signal, a digital CVBS format or a
luminance format (S-VHS, HI8), is fed through a
switchable prefilter. High frequency components are
emphasized to compensate for loss. The following
chrominance trap filter (f0 = 4.43 or 3.58 MHz centre
frequency set according to the selected colour standard)
eliminates most of the colour carrier signal. It should be
bypassed via I2C-bit BYPS (subaddress 09H, bit 7) for
S-video (S-VHS, HI8) signals.
MGD139
18
handbook, full pagewidth
V
Y
(dB)
(1)
6
−6
(2)
(4)
(3)
(1)
(2)
(4)
(3)
−18
−30
0
2
4
6
8
f
Y (MHz)
(1) 43H.
(2) 53H.
(3) 63H.
(4) 73H.
Fig.11 Luminance control SA 09H, 4.43 MHz trap/CVBS mode, prefilter on, different aperture band-pass centre
frequencies.
1999 Jul 01
16
NXP [ NXP ]
