Switched-transconductance techniques: a new approach for tunable, precision analogue sampled-data signal processing

A new circuit arrangement, described as a switched transconductance (ST) circuit, comprising a continuous-time linear tunable transconductor and a discrete-time current processor is proposed. The circuit presents an input impedance which is equal to the inverse of the product of the transfer functions of the transconductor and current processor. This concept relates to a method for facilitating the accurate and continuously tunable processing of sampled-data analog signals in a fully integrable manner, without the need for post-manufacture trimming. The theoretical basis for the technique is presented.