Feedforward technique for offset cancellation in broadband differential amplifiers

Abstract

This paper presents a new feedforward offset cancellation technique for broadband amplifiers which are used in high speed communication systems. Unlike other conventional techniques, such as feedback cancellation or AC coupling, the proposed technique eliminates the need for larger area passive components and avoids the potential stability issue by eliminating the feedback path. Implementing in 90nm CMOS, the broadband amplifier achieves 52.3 dB gain and 2.7 GHz 3-dB bandwidth with more than 50 dB DC offset rejection.