Analog Devices, Inc.
Current mirror arrangements with double-base current circulators

Abstract:

A current mirror arrangement with a current mirror and a double-base current circulator is disclosed. The current mirror is configured to receive an input current (I.sub.IN) and generate a mirrored current (IM), where IM=K*I.sub.IN. The current circulator, coupled to the current mirror, is configured to convey the mirrored current to an output node of the arrangement. The current circulator is a double-base current circulator and includes a first branch configured to receive a first branch current (I1b), where I1b=m*IM, where m is a positive number less than 1, and further includes a second branch configured to receive a second branch current (I2b), where I2b=(1-m)*IM. The first branch includes a cascode of transistors Q3 and Q5, configured to provide I1b to an output node. The second branch includes a transistor Q4 configured to provide I2b to the output node, where it is combined with I1b.