BANDGAP VOLTAGE REFERENCE CIRCUIT WITH AN NPN CURRENT BYPASS CIRCUIT

摘要

A temperature compensated bandgap voltage reference circuit employs an npn transistor based bypass circuit to maintain a constant collector current within the reference circuit. This bypass circuit draws a nominal current from the bandgap voltage reference circuit. The value of this current is set by a bias circuit responsive to changes in the supply voltage. As the supply voltage changes, the bias circuit varies, the conductance of a bypass transistor to draw more or less current and thereby maintain the collector current within the reference circuit constant.