A micropower CMOS continuous-time low-pass filter

A continuous-time third-order Butterworth low-pass filter with a nominal cutoff frequency of 945 Hz implemented in a standard 2.4- mu m CMOS process is discussed. The filter is built from fully balanced linearized transconductors and capacitors. The power consumption of the filter, including bias and automatic-tuning circuits, is 12.6 mu W from a single 3-V power supply. It achieves a dynamic range of 63 dB with a total harmonic distortion of less than 0.5%. The total chip area is 1 mm/sup 2/.<
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