The Design Of High-Performance BiCMOS Bandgap Voltage Reference

With the development of semiconductor process and circuits design technology, analog integrated circuit improved greatly in recent years.There is a challenge to the performance of circuits.Bandgap reference voltages are important analog circuit blocks.It can provide a nearly constant reference voltage which is stabilized over temperature, power supply and process variation.lt makes the bandgap reference voltage be used extensively.But it generated reference voltage accuracy, anti-jamming, temperature stability and other parameters directly affect the performance of power.Therefore, high-performance bandgap reference design has practical engineering significance.Based on the basic principle of bandgap reference, design a high precision, high power supply rejection ratio(PSRR) and low temperature coefficient (TC) bandgap voltage reference.The bandgap reference voltage which is designed include the core circuit, operational amplifier (op amp), bias circuit and start circuit four parts.Core circuit is on basis of Brokaw bandgap reference circuit design.Op amp is designed with the input bipolar transistor, MOSFET to provide bias of two differential op amp circuit.Bias circuit is designed with low-voltage common source-cascade current mirror and low self-bias of the source-cascade current mirror.Start circuit with the inverter circuit, starts automatically disconnect the circuit to reduce power consumption.To further improve the design of bandgap voltage reference performance, first use exponential curvature compensation technique to reduce the temperature coefficient, then the negative feedback loop to improve access to low-frequency PSRR, and then on the basis join the common-gate MOSFET shielded power in fluence, and finally access the output RC filter circuit, to improve the high frequency PSRR.TSMC 0.6μm BiCMOS skill is used for the bandgap reference voltage with the simulation tool of HSPICE.Simulation results show that the TC with temperature ( 40℃-100℃) is 7.2 ppm/℃, and with the 3.3 V power supply voltage and 25℃temperature, the power supply regulation is about 0.23 mV/V.ln the frequency range 10 Hz-1 GHz, the average PSRR has reached more than 100 dB.When the supply voltage 2.5 V-5 V range of changes, bandgap reference produces an output voltage of 997.6 mV.Quiescent current is 1.6 nA and start time is 500μs.Noise is less than 65 nV (Hz)^1/2.These indicators have reached the goal of circuit design.Thus, the design of bandgap voltage reference circuit has a high PSRR, low TC of technical advantages.