TECHNOLOGICAL COMPENSATION CIRCUIT FOR ACCURATE TEMPERATURE SENSOR

A compensation circuit has been developed to reduce the V-BE wafer spr ead of a bipolar transistor by taking advantage of the correlation bet ween pinched base resistor R-P and I-S of the Ebers-Moll model. This c ompensation circuit was used in the design of a Celsius temperature se nsor with intrinsic reference, improving its accuracy at least five ti mes within the 0 degrees C to 100 degrees C interval. Accuracy has bee n calculated considering wafer level statistical modeling of bipolar I C parameters, circuit sensitivity, and worst case circuit simulation. This technological compensation procedure allows to obtain an accurate IC temperature sensor without final trimming at wafer level. (C) 1998 Elsevier Science S.A. All rights reserved.