A bandgap reference is designed with high order curvature compensation method

which has advantages of simple structure

good energy dissipation capacity and an optimized temperature coefficient of the reference voltage. Taking advantage of the nonlinear characteristics between leakage current and gate-source voltage when NMOS is working in the sub-threshold region

the proposed method decreases the temperature coefficient of reference voltage by introducing a high order curvature compensation current of which the temperature coefficient is contrary to reference. The formula of the compensated reference voltage is derived. Based on the 0.18 μm BCD process

the simulation results show that temperature coefficient of reference is 6.94×10-6 in the temperature range of -40 ℃~150 ℃

linear regulation rate is 0.033% in the supply voltage VDD range of 2.5~5.0 V

the supply current is 7.36 μA with 5V power supply

the power supply rejection ratio(PSRR) is 77.4 dB at the Tipical corner(TT). The theoretical analysis results of reference agree well with the simulated results. The bandgap reference voltage source shows excellent performance vias the high order compensation

which satisfies the requirement of low power consumption and low temperature drift in bandgap reference designing.