1.5 V tunable Square-Root Domain filter

A novel approach to the design of low-voltage CMOS Square-Root Domain filters is presented. It is based on the largesignal behaviour of a well-known class-AB linear transconductor. A first-order filter is built employing three such transconductors, featuring simplicity and compactness. Measurement results for an experimental prototype in 0.8 (mu)m CMOS validate the technique proposed. The filter operates with a single supply voltage of 1.5 V and can be tuned in more than one decade.