VLSI implementations of switched-capacitor filter

This paper presents efficient designs and implementations of switched-capacitor (SC) filters. We design two switched-capacitor filters, with a 6 MHz bandwidth and an input sampling frequency of 13.5 MHz, using 0.35 μm CMOS technology (V_tn=0.56 V, V_tp=-0.77 V, V_dd=1.65 V, V=-1.65 V). We considered several approaches to design SC filters, and implemented two circuits suitable for video applications. The first filter is designed using a switched-capacitor integrator with an inductor, which achieves a bandwidth of 0.25 MHz to 6.25 MHz with a center frequency of 1.7 MHz. The switched-capacitor integrator with an inductor has a good pass-band gain but a high center frequency. The second circuit is designed using a multiple feedback band-pass filter, which achieves a bandwidth of 0.25 MHz to 6.25 MHz with a center frequency of 1.27 MHz. The advantage of the multiple feedback band-pass filter design is the low center frequency over specified bandwidth but a poor pass-band gain. The two designed SC filters require less area and consume less power.