A highly linear CMOS G/sub m/-C bandpass filter with on-chip frequency tuning

摘要

A fourteenth-order CMOS transconductance-C (G/sub m/-C) bandpass filter with on-chip automatic frequency tuning is described. By using highly linear G/sub m/-C integrators, the filter achieves 75 dB dynamic range over 700 kHz noise bandwidth. The measured intermodulation distortion (IM3) @ 600 kHz for a 4 V/sub pp/ input signal is only -61 dB. On-chip automatic frequency tuning provides more than 300% center frequency range (i.e., 165-505 kHz) of the filter with /spl plusmn/1% frequency accuracy. The 0.7-/spl mu/m CMOS filter measures 4.8 mm/sup 2/ and consumes 70 mW from a single 5 V power supply.