Low-voltage current mirror circuit and method

摘要

A current mirror circuit is provided that has a feedback loop that includes a current mirror that provides base current compensation to the bases of the input and output transistors of the current mirror circuit. By employing a current mirror in the feedback loop to provide base current compensation, the minimum power supply voltage of the current mirror circuit is very low, typically less than or equal to about 1.5 V.

主权项

1. A low-voltage current mirror circuit comprising:
at least a first power supply voltage source supplying a supply voltage to the current mirror circuit; an input stage electrically coupled to the power supply voltage source, the input stage comprising at least a current source and a first transistor; an output stage having an input node that is electrically coupled to an output node of the input stage, the output stage comprising a second transistor that operates as a first current mirror to the first transistor; a three-terminal voltage controlled current source (VCCS) having a first terminal, a second terminal and a third terminal, the first terminal of the VCCS being electrically coupled to the input stage, the second terminal of the VCCS being electrically coupled to ground; and a feedback loop electrically coupled on a first end to the third terminal of the VCCS and on a second end to the output and input nodes of the input and output stages, respectively, the feedback loop including a second current mirror that provides a compensation current to the output and input nodes of the input and output stages, respectively.