Since traditional bandgap reference could not meet the high performance requirements for temperature sensor,a voltage reference source was designed with low temperature drift and high power rejection ratio,which was based on voltage mode bandgap reference using SMIC018 technology.The second-order curvature compensation of temperature was achieved by adding a resistor between the base and the ground of the bipolar transistor,and the temperature drift coefficient was also reduced by using the approximate linear relationship between the current amplification factor β and temperature in BJT transistor.Compared with the existing second-order temperature compensation technology,it has the advantages of simple structure,low power consumption and better compensation effect.Meanwhile,the PSRR enhancement circuit and the RC filter circuit were used to improve the power rejection ratio of the bandgap reference voltage source.Simulation results show that the temperature drift coefficient is 9.786 ×10-6/℃ and 3.03 ×10-6/℃ before and after compensation.At low frequency,the power supply rejection ratio is-104 dB,and the PSRR can achieve more than 100 dB in the full frequency between 1 Hz and 1 GHz,and the power consumption is only 0.039 mW.The reference source can be applied to the temperature sensor chips that require low temperature drift and high PSRR.
关键词
温度传感器/带隙基准电压源/二阶曲率补偿/电源抑制比/低温漂
Key words
temperature sensor/bandgap reference voltage source/second order curvature compensation/power supply rejection ratio/low temperature drift
维普
万方数据