A study of the out-of-band interference of negative-feedback amplifiers is carried out in this thesis. Several design methods to reduce the susceptibility to interference are identified and developed. The proposed techniques are based on robust circuits and topologies that are suitable for monolithic integration.

The effect of second-order intermodulation (IM2) distortion produced by out-of-band, high-frequency interference on baseband/IF amplifiers is analyzed using the Volterra series. It is shown that a compensation loop designed to trap nonlinear currents improves the immunity of differential stages to IM2 distortion generated by local feedback. Measurements of a single-ended amplifier example implementing the proposed method demonstrate an IP2 increase of more than 30 dB