June 1994

17

Philips Semiconductors

Product specification

Video analog input interface

TDA8708A

Fig.13 Example of a low-pass filter for CVBS and Y signals.

This filter can be adapted to various applications with respect to performance requirements. An input and output impedance of at least 680

Ω and 2.2 kΩ

must in any event be applied.

dbook, full pagewidth

MBB966 - 1

27 pF

68 pF

27 pF

2.2 k

Ω

12 pF

12 pF

22

µH

ANOUT

(pin 19)

ADCIN

(pin 20)

Vo

V i

VCCA

(pin 22)

680

Ω

22

µH

Fig.14 Frequency response for filter shown in

Fig.13.

handbook, halfpage

010

30

0

40

120

160

80

MSA682

20

f (MHz)

α

(dB)

Characteristics of Fig. 13

• Order 5; adapted CHEBYSHEV

• Ripple ρ≤ 0.4 dB

• f = 6.5 MHz at −3dB