SAA7118 Datasheet, PDF (18/169 Pages) NXP Semiconductors – Multistandard video decoder with adaptive comb filter and component video input

Philips Semiconductors
Multistandard video decoder with adaptive
comb filter and component video input
Preliminary specification
SAA7118
8 FUNCTIONAL DESCRIPTION
8.1 Decoder
8.1.1 ANALOG INPUT PROCESSING
The SAA7118 offers sixteen analog signal inputs, four analog main channels with source switch, clamp circuit, analog
amplifier, anti-alias filter and video 9-bit CMOS ADC with a Decimation Filter (DF); see Figs 5 and 8.
The anti-alias filters are adapted to the line-locked clock frequency via a filter control circuit. The characteristic is shown
in Fig.4. During the vertical blanking period gain and clamping control are frozen.
6
V
(dB)
0
−6
−12
−18
−24
−30
−36
−42
0
2
4
MGD138
6
8
10
12
14
f (MHz)
Fig.4 Anti-alias filter.
2001 May 30
18