Precise Wide-Dynamic Range Constant Current Ratio Circuits

A method of compensation of unequal VBE's, in a conventional constant current ratio circuit is proposed, which improves the accuracy and the dynamic range of the current ratio considerably, without the need to use any higher resistance than normally desirable for integrated circuits. The linearity of the current ratio is better than 1 percent over a dynamic range of greater than four orders of magnitude. Copyright © 1977 by The Institute of Electrical and Electronics Engineers, Inc.