RFR SERIES ANTIALIASING FILTERS These filters are designed especially for use in systems where composite video signals are digitised. A sampling frequency of four times the colour subcarrier frequency is normally used as with D2 systems. The filters have a bandwidth of 5.5 MHz for 625 line systems, a stopband attenuation of 50 dB after 11.75 MHz and a zero at the sampling rate of 17.72 MHz. The attenuation at the sampling frequency is approximately 80 dB so minimising aliasing effects. The relatively slow roll-off and controlled group delay over the whole of the passband minimises time domain ringing ensuring the system has an excellent performance. Flat (pre filter) and sinx/x (post filter) versions are available. The module is 40 pin DIL suitable for direct mounting in a pcb. Ground pins should be taken to separate earth points to maintain transmission line characteristics if the full stopband performance is required. Type Number RFR1772F RFR1772S Filter Shape Passband Shape Sampling Frequency Attenuation at S.F. wrt 100 kHz Insertion Loss at 100 kHz End Of Passband Passband Ripple wrt 100 kHz Loss at half S.F. wrt 100 kHz Start Of Stopband Stopband Attenuation Group Delay Ripple wrt 200 kHz Group Delay Bandwidth Delay Time at 200 kHz Pulse And Bar K - Rating Luminance / Chrominance Gain Luminance / Chrominance Delay Impedance Temperature Range Aqueous washable Package Type Lowpass Lowpass Flat Sinx/x 17.72 MHz 17.72 MHz > 70 dB > 70 dB < 0.8 dB < 2.5 dB 5.5 MHz 5.5 MHz + 0.10 dB + 0.15 dB 18.0 dB 16.5 dB 11.75 MHz 11.75 MHz > 50 dB > 50 dB + 5.0 ns + 5.0 ns 5.5 MHz 5.0 MHz 250 ns nom 240 ns nom < 0.5 % < 0.5 % <2% n/a < 5 ns < 5 ns 75 ohms 75 ohms 0°C to 70°C 0°C to 70°C Yes Yes DR00020B DR00020B © Faraday Technology. As part of continual product improvement the specifications, details and dimensions shown in this publication are subject to change without notice FARA158d Page 1 of 2 Dec-99(A) PACKAGE DETAIL Faraday Technology Ltd. Croft Road Industrial Estate, Newcastle, Staffordshire ST5 0QZ. England. FARA158d Tel: Fax: Email: Web site: Page 2 of 2 + 44 (0)1782 661501 + 44 (0)1782 630101 [email protected] http://www.faradaytech.co.uk Dec-99(A)