A CMOS gm-C IF filter for Bluetooth

In English An 18th (4th+14th) order gm -C IF filter for the Bluetooth short-range radio, implemented in a 0.6 μm CMOS process, is presented. The filter bandwidth is 1 MHz, the center frequency fc is 3 MHz, the in-band group delay variation is 0.75 μs, and the stop-band attenuation at fc±1 MHz is at least 47 dB. The noise floor is 250 μVr.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