Design of high precision CMOS voltage reference

Abstract

a stable bandgap CMOS voltage reference is designed for LED driver by combining with self-starting circuit and multi-valued bias voltage generating circuit modules. The circuits are designed by using CSMC 0.5µm CMOS process. Simulation results by Cadence software show that the temperature coefficient is about 10ppm/°C, zero temperature coefficient is about at 31°C, close to room temperature. And good temperature characteristics can be achieved in practical applications. Meanwhile, power supply rejection ratio is up to 80dB, which can meet the requirement of LED driver IC.