A high-Q and wide-dynamic-range CMOS IF bandpass filter for monolithic receivers

Design of a 6-th-order CMOS G(m)-C bandpass filter with automatic tunning for IF filtering in monolithic receivers is presented. A linearized transconductance (G(m)) cell is designed and optimized for both noise and linearity. The G(m) cells of the biquads and the tuning circuitry are implemented using generic G(m) cells for better matching and less power consumption. The filter prototype achieves a measured bandwidth of about 200 KHz at 50.5 MHz (Q = 250) and 3.5 MHz at 70 MHz (Q = 20). The measured input equivalent noise is 36.3 mu V and the IIP3 is -10 dBm, which corresponds to a dynamic range of about 66 dB. At 2.5 V, the total power consumption is 120 mW.