ULTRA-LOW NOISE VOLTAGE REFERENCE CIRCUIT

摘要

A voltage reference circuit comprises a plurality of &Dgr;VBE cells, each comprising four bipolar junction transistors (BJTs) connected in a cross-quad configuration and arranged to generate a &Dgr;VBE voltage. The plurality of &Dgr;VBE cells are stacked such that their &Dgr;VBE voltages are summed. A last stage is coupled to the summed &Dgr;VBE voltages and arranged to generate one or more VBE voltages which are summed with the &Dgr;VBE voltages to provide a reference voltage. This arrangement serves to cancel out first-order noise and mismatch associated with the two current sources present in each &Dgr;VBE cell, such that the voltage reference circuit provides ultra-low 1/f noise in the bandgap voltage output.