Canceling third order non-linearity in current mirror-based circuits

摘要

A current mirror circuit is described. The current mirror circuit includes a first transistor and a second transistor. The gates of the first transistor and the second transistor are coupled at a bias voltage. The current mirror circuit also includes an auxiliary transistor that is biased into weak inversion by receiving the bias voltage at a gate of the auxiliary transistor after being reduced by an offset voltage. The sources of the first transistor, second transistor and auxiliary transistor are coupled together. A primary current from the drain of the second transistor is combined with an auxiliary current from the drain of the auxiliary transistor to produce an output current.

主权项

1. A current mirror circuit, comprising:
a first transistor and a second transistor, wherein gates of the first transistor and second transistor are coupled at a bias voltage; a voltage offset circuit including at least one operational amplifier, wherein the at least one operational amplifier is arranged to reduce the bias voltage by an offset voltage; and an auxiliary transistor that is biased into weak inversion by receiving the reduced bias voltage at a gate of the auxiliary transistor, wherein sources of the first transistor, second transistor and auxiliary transistor are coupled together, wherein a primary current from a drain of the second transistor combines with an auxiliary current from a drain of the auxiliary transistor to produce an output current, wherein the output current constitutes an output of a baseband filter.