Patent Number: 8,816,770

Title: Low-voltage constant-gm rail-to-rail CMOS input stage with improved gain

Abstract: The present invention concerns an apparatus comprising a first circuit and a second circuit. The first circuit may be configured to generate an output signal in response to a differential input signal, a first power supply and a ground. The output signal may have a rail-to-rail voltage with a magnitude between the first power supply and the ground. The first circuit may also be configured to source an intermediate differential signal in response to the differential input signal, the first power supply and ground. The second circuit may be configured to sink the differential intermediate signal in response to the differential input signal, the first power supply, ground and a second power supply. The second circuit may flatten the transconductance of the first circuit relative to a common mode voltage of the differential input signal.

Inventors: Pradhan; Kishan (Bangalore, IN)

Assignee: LSI Corporation

International Classification: H03F 3/45 (20060101)

Expiration Date: 8/26/12018