Design of a Bandgap Reference Source with Chopper Modulation
To reduce the impact of offset voltage and noise on traditional bandgap references,a low temperature drift,low noise,high-precision voltage bandgap reference is proposed using SMIC40 nm CMOS process.Temperature coefficient modulation resistors and output voltage divider resistors are trimmed using resistor matrices to minimize the process impact on temperature coefficient and bandgap reference voltage.Chopper modulation combined with a low-pass filter is employed to significantly reduce the influence of offset voltage and noise on the reference voltage.Simulation using Cadence Spectre tools shows that with a 3.3 V power supply under typical conditions,the temperature coefficient of the output voltage is 5.87×10-6/℃over a temperature range of-40 ℃ to 125 ℃.After incorporating the chopper circuit,noise is significantly reduced compared to ordinary bandgap references,and relative accuracy is improved by 50 times.
Bandgap referenceTemperature coefficientChopper modulationPower supply rejection ratio
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维普
