FL476 / FL477 LOW COST MULTIMEDIA RECONSTRUCTION These filters are designed to be used with Half-band Interpolating/Decimating digital filters, for example the TRW TMC2242, or with devices employing an output D/A which incorporates digital filters such as the TRW Digital Video Encoder TMC22190. The digital filters have good attenuation between the frequencies of Fs/4 and 3Fs/4 where Fs is the PXCK (Master clock) rate and, combined with double speed oversampling, this simplifies the specification for the analogue reconstruction and antialiasing pre filters as when the normal PXCK rate of 27 MHz is used there is little signal energy between 6.75 MHz and 20.25 MHz. To reconstruct the analogue signal an additional filter is required to attenuate the clock frequency and its sidebands. To preserve the integrity of the signal the analogue filter must have a passband similar to the requirement of CCIR rec 601 but it does not need significant attenuation below 21 MHz. An additional feature in the Faraday filters is a zero at 27 MHz to maximise suppression at the PXCK rate. Sinx/x correction may be added by grounding one pin in the device. Filter Shape Sinx/x correction Sampling Frequency End Of Passband Passband Amplitude Ripple to 5.5 MHz to 5.75 MHz Start Of Stopband Stopband Attenuation wrt 100 kHz Group Delay Ripple Group Delay Bandwidth Delay Time at 200 kHz Flat mode Sinx/x mode Impedance Temperature Range Aqueous Washable Package FL476 FL477 Through hole connections Lowpass Pin selectable 27 MHz 5.75 MHz Surface mount Lowpass Pin selectable 27 MHz 5.75 MHz < 0.05 dB < 0.1 dB < 0.05 dB < 0.1 dB 21.5 MHz > 40 dB < 6 ns 5.75 MHz 58 ns nominal 55 ns nominal 75 ohms 0°C to 70°C Yes DR00030A 21.5 MHz > 40 dB < 6 ns 5.75 MHz 58 ns nominal 55 ns nominal 75 ohms 0°C to 70°C Yes DR00055A © Faraday Technology. As part of continual product improvement the specifications, details and dimensions shown in this publication are subject to change without notice FARA053d.DOC Page 1 of 2 Mar-01(C) PACKAGE DETAIL Faraday Technology Ltd. Croft Road Industrial Estate, Newcastle, Staffordshire ST5 0QZ. England. FARA053d.DOC Tel: Fax: Email: Web site: Page 2 of 2 + 44 (0)1782 661501 + 44 (0)1782 630101 [email protected] http://www.faradaytech.co.uk Mar-01(C)