A design of CMOS bandgap reference with low thermal drift and low offset

This paper presents a high performance bandgap voltage reference, together with the discussion of the principle of the quadratic temperature compensation. The circuit utilizes two resistors made of different materials to compensate the quadratic temperature, so as to efficiently reduce the temperature drift of the bandgap voltage reference. To reduce the offset voltage, the improved design methods for circuit and layout are introduced. The cascode structure is also introduced in this bandgap voltage reference circuit to improve the power supply rejection ratio (PSRR). Finally the simulation results based on 0.35 mum CMOS process show that the temperature coefficient is 3.5 ppm/degC And after MPW manufacture and testing, the result achieves our targets.