New realization of inductances for switched-capacitor filters using voltage inverter switches

This paper describes a new design method of inductance simulation for switched-capacitor (SC) filters based on the VIS-SC concept. The resulting circuits have not only the excellent sensitivity behavior of VIS-SC filters, but also the low sensitivity to the main parasitics occuring in the MOS integrated circuit, i.e., the parasitic capacitances between the bottom plates of the implemented capacitors and substrate. As examples, a sixth-order band-pass and a sixth-order band-stop elliptic filter transformed from a third-order low-pass are given. Experimental results agree very well with theory. A brief analysis is given of certain parasitic effects in band-stop filters at the Nyquist frequency.