A Design of Passband-chosen Complex Filter and Automatic Calibration System

Abstract

A low power design of active RC complex filter was proposed by using 130nm CMOS process. The filter has 4 center frequencies, 100 kHz, 200 kHz, 300 kHz and 500 kHz. The image rejection is higher than 40dB. An automatic calibration system with dichotomy algorithm and RC oscillator circuit was used to caliber both the center frequency and the band-wide. The circuit consumption of the filter and the calibration system is less than 500uA with 1.5Vsupply voltage and the calibration error is less than 1%.