Design And Research Of Low-Temperature Coefficient Low-Power Bandgap Voltage Reference

As an important component of analog integrated circuits,the reference source plays a crucial role in providing stable and accurate voltage or current references to other circuit modules.Its output signal should remain stable in the face of temperature variations,power supply voltage fluctuations,process differences,and load changes.With the rapid development of semiconductor technology and the continuous improvement of circuit system performance,the quality of the reference source as a core module directly affects the stability of the entire circuit system.Different chips have their own requirements for the performance indicators of the bandgap reference voltage source,so optimizing one indicator while considering other indicators is necessary.Therefore,research on high-performance bandgap reference sources is of great importance.In this paper,a bandgap reference voltage source circuit was designed targeting low temperature coefficient and power consumption.In this paper,the traditional CMOS type bandgap reference circuit structure is improved,and the common-source common-gate structure of the operational amplifier is used in the bandgap reference source circuit to achieve higher gain,and then a new high-order compensation circuit is designed by using resistance proportional compensation technology,on the basis of first-order compensation,a new branch is added by the operational amplifier,and the high-order compensation is realized by resistors and transistors,which is used to offset the high-order term of the base-emitter voltage of the bipolar transistor.In addition,resistance feedback is added to the first-order compensation and high-order compensation,and the output voltage is adjusted through resistance,thereby reducing the temperature coefficient.The final output voltage of the entire circuit is a weighted superposition of two voltage parts,one part of which is the PTAT current generated by the bandgap reference core circuit,which is achieved by the first-order temperature compensation of the reference core circuit to provide the reference voltage.The other part of the voltage is generated by the higher-order compensation circuit to compensate for the influence of the higher-order temperature coefficient in the reference core circuit,and the two parts of the voltage are weighted and superimposed to achieve a bandgap reference circuit with a low temperature coefficient.The circuit design,pre-simulation,layout design,and post-simulation were implemented using the TSMC 180 RF standard CMOS process.Cadence Spectre was utilized to perform pre-simulation and post-simulation for temperature coefficient,linearity adjust rate,power supply rejection ratio,and DC power consumption under three different process corners.The simulation results show that over the temperature range of-30°C to 125°C,the temperature coefficient can be as low as9.66ppm/°C.The circuit exhibits a linear adjustment rate of 1.3μV/V,a low-frequency power supply rejection ratio of-84 d B,a static current of 165.95μA,and a layout area of 200×120μm.