A CMOS complex Gm — C filter for low-IF bluetooth receiver

A Bluetooth low-intermediate frequency complex channel filter has been designed using 0.25¿m CMOS technology model. The filter is based upon transconductor-capacitor structure. The filter is implemented using a balanced output transconductor with an extended range of input voltage and enhanced linearity. The filter is based on a 6
^th
order lowpass Butterworth approximation, has a bandwidth of 1 MHz and center frequency of 2 MHz. The filter operates from balanced supplies of ±1.5v. Simulations results of the implemented complex filter are presented in this paper. Simulations are carried out using PSpice. The simulation results were found to be in good agreement with theoretical expectations.