Programmable Filters Suited For Use With 16-Bit A/D Converters

The 424 and 428 Series of 4-bit, digitally programmable 4- and 8-pole filters can provide -100 dB attenuation, noise and distortion floors sufficient for 16-bit A/D converters. And they can accomplish this in a package that uses 60% less space than previous 824 and 828 solutions. With dimensions of 0.8” x 1.8” x 0.3” and a 28-pin DIP footprint, the filters include Butterworth, Bessel, elliptic and constant delay transfer functions. Butterworth and elliptic filters are also available in high-pass, band-pass and band-reject versions. The devices also offer a choice of preset binary or discrete (maximum 1000:1) frequency tuning ranges to 102.4 kHz.