Gain enhancement for cascode structure

摘要

Aspects of the present invention provide apparatuses and methods to provide significant gain enhancement for a cascode structure for a differential amplifier. The cascode structure of the differential amplifier can include first and second pairs of output transistors. The second pair of output transistors can be configured to approximately cancel modulation effects of the first pair of output transistors induced by changes in a differential output of differential amplifier, thereby resulting in conditions for providing enhanced gain.

主权项

1. An amplifier, comprising:
a first transistor and a second transistor; a third transistor and a fourth transistor,
a source of the third transistor coupled to a drain of the first transistor,a gate of the third transistor directly coupled to a drain of the third transistor,a source of the fourth transistor coupled to a drain of the second transistor,a gate of the fourth transistor directly coupled to a drain of the fourth transistor, and a fifth transistor and a sixth transistor,
a source of the fifth transistor coupled to the drain of the first transistor,a drain of the fifth transistor coupled to the drain of the third transistor,a source of the sixth transistor coupled to the drain of the second transistor,a drain of the sixth transistor coupled to the drain of the fourth transistor, wherein a gate of the fifth transistor is coupled to the drains of the fourth and sixth transistors and a gate of the sixth transistor is coupled to the drains of third and fifth transistors.