A precision curvature-compensated CMOS bandgap reference

Abstract

A precision curvature-compensated switched-capacitor bandgap reference is described which uses a standard digital CMOS process and achieves temperature stability significantly lower than has previously been reported for CMOS circuits. The theoretically achievable temperature coefficient approaches 10 ppm//spl deg/C over the commercial temperature range and uses a straightforward room temperature trim procedure. Experimental data from monolithic prototype samples are presented which are consistent with theoretical predictions. The experimental prototype circuit occupies 3500 mil/SUP 2/ and dissipates 12 mW with /spl plusmn/5 V power supplies. The proposed reference is believed to be suited for use in monolithic data acquisition systems with resolutions of 10 to 12 bits.