Design And Research Of Reference Voltage Source With Low Voltage And Low Temperature Drift

A reference voltage source is a widely used module in most integrated circuits,which provides DC bias independent of process,supply voltage,and temperature(PVT).The traditional bandgap reference produces an output voltage of about 1.25 V and a temperature coefficient generally higher than 20 ppm/ ℃.As the supply voltage of modern short channel devices becomes smaller and smaller,the requirements for the stability of the reference PVT in high-precision modules gradually increase.Therefore,reference voltage sources with low voltage output and low temperature drift coefficient have broad application prospects and requirements.The reference voltage source in thesis adopts a Banba structure,which can provide output below the bandgap voltage.A temperature compensation circuit is designed,using MOSFET in weak inversion regions to achieve temperature compensation,and using linear region MOS transistors to replace resistors.Compared to traditional temperature compensation methods,it saves layout area and power consumption.A pre regulator is designed,which greatly improves the PSRR compared to traditional bandgap reference.Finally,the layout design and post simulation verification are performed according to the whole circuit.The design stems from Cadence Virtuoso platform with 65 nm CMOS process.The simulation results reveal that the export of reference source is 752 m V,which can reach a temperature coefficient of 1.56ppm/℃ within the temperature range of-55～125℃.And the PSRR is higher than 90 d B in the low frequency band.The voltage source performs well under all process corners.