Design Of A Low Voltage Bandgap Reference Circuit

Bandgap reference,as a basic circuit module,can generate reference voltage or reference current which is very small relative to ambient temperature,power supply voltage and process parameters.As the characteristic size of the integrated circuit technology gets closer to the minimum theoretical limit of silicon,the power supply voltage of the chip is gradually reduced.The traditional bandgap reference has been unable to work under the power voltage of less than 1.8V.At the same time,with the wide application of integrated circuits in portable devices and high-precision systems,it has higher requirements on the indexes of bandgap reference source.In this paper,the development history and basic principle of band-gap reference source are introduced.On this basis,this paper present the mainstream of development trend,designed a reference voltage is 800 m V?700mV,temperature coefficient is less than 10 PPM/ ? low-pressure quick start band gap reference source.The circuit adopts SMIC0.18 library mu m process,and the curvature compensation and the threshold value compensation method,the simulation results show that the in-40 ? to 125 ? temperature range,the band gap reference only 0.37 mV changes,output voltage temperature coefficient as low as2.79ppm/ ?;When power supply voltage from 1.4 V to 2.2V range change,band gap reference output voltage change 0.18 mV;Power supply voltage rejection ratio is-74.90 dB.The result shows that the design of this circuit basically meets the design requirements.