A novel CMOS Bandgap reference circuit with improved high-order temperature compensation

Abstract

This paper proposes a new CMOS bandgap reference generator topology that allows a straightforward implementation of an exact curvature compensation method by using only poly-silicon resistors. This is achieved by using a second Opamp that generates a CTAT current, which is subsequently used to enhance the curvature compensation method. A superior theoretical performance than previously proposed architectures is achieved with respect to temperature sensitivity of the reference voltage. In nominal simulations, that was less than 0.lppm over a temperature range of -40 to 125 for a CMOS 0.35 μm technology. In practice, the proposed BGR is sensitive to device mismatch and thus resistor trimming is necessary if high performance is required.