Low distortion filters

摘要

An integrated continuous-time active-RC filter comprises a set of opamp integrators with Operational Transconductance Amplifiers (OTAs), and at least one assistant transconductor connected between an input and an output of each of the integrators of the set; wherein the assistant transconductor comprises a plurality of sets of MOSFETS connected in parallel to each other wherein each set of MOSFETS is formed by a pair of MOSFETs connected in series, with one MOSFET of the pair operating in the triode region and the other MOSFET of the pair operating in the saturation region; and wherein the assistant transconductor is configured to inject an assistant current into the output of each of the integrators in the set to enhance the linearity and speed of the opamp integrators of the set.

主权项

1. An integrated continuous-time active-RC filter comprising a set of opamp integrators with Operational Transconductance Amplifiers (OTAs); said filter characterized by:
at least one assistant transconductor being connected between an input and an output of each of the integrators of the set, said at least one assistant transconductor adapted to inject an assistant current into the output of each of the integrators in the set, to enhance the linearity and speed of the opamp integrators of the set; wherein said at least one assistant transconductor comprises:
a plurality of sets of MOSFETS connected in parallel to each other;each set of MOSFETS being formed by a pair of MOSFETS connected in series, said pair of MOSFETS connected in series comprising a first MOSFET operating in the triode region and a second MOSFET operating in the saturation region.