A CMOS g/sub m/-C IF filter for Bluetooth

Abstract

An 18/sup th/ (4/sup th/+14/sup th/) order g/sub m/-C IF filter for the Bluetooth short-range radio, implemented in a 0.6 /spl mu/m CMOS process, is presented. The filter bandwidth is 1 MHz, the center frequency f/sub c/ is 3 MHz, the in-band group delay variation is 0.75 /spl mu/s, and the stop-band attenuation at f/sub c//spl plusmn/1 MHz is at least 47 dB. The noise floor is 250 /spl mu/V/sub r.m.s./ and the spurious free dynamic range is at least 58 dB for out-of-band signals, thus exceeding the Bluetooth requirements. Current consumption is 2.4 mA from a 2.5 V power supply.