Philips Semiconductors
Preliminary specification
PAL/NTSC/SECAM video decoder with adaptive PAL/NTSC
comb filter, VBI-data slicer and high performance scaler
SAA7114H
8
FUNCTIONAL DESCRIPTION
Decoder
8.1.2
ANALOG CONTROL CIRCUITS
8.1
The anti-alias filters are adapted to the line-locked clock
frequency via a filter control circuit. The characteristics are
shown in Fig.3. During the vertical blanking period, gain
and clamping control are frozen.
8.1.1
ANALOG INPUT PROCESSING
The SAA7114H offers six analog signal inputs, two analog
main channels with source switch, clamp circuit, analog
amplifier, anti-alias filter and video 9-bit CMOS ADC;
see Fig.6.
MGD138
6
handbook, full pagewidth
V
(dB)
0
−6
−12
−18
−24
−30
−36
−42
0
2
4
6
8
10
12
14
f (MHz)
Fig.3 Anti-alias filter.
2000 Mar 15
13