A Low-power CMOS Voltage Reference With Load Capability

As the most basic and important module in analog and mixed analog-digital circuits,voltage reference source plays the role of providing accurate and stable reference voltage in the whole circuit.Therefore,the voltage reference source is widely used in modern large-scale integrated circuit and modern very large scale integrated circuits,such as power management systems,phase lock loop,ADC,DAC,environmental sensors and wireless sensor network?WSN?,etc.This paper innovatively proposes a low power sub-threshold CMOS voltage reference with current loading capability by analyzing the working principle and performance index of the classical 2T sub-threshold CMOS voltage reference.The research on circuits of traditional 2T sub-threshold CMOS voltage reference includes circuit principle analysis and simulation analysis of performance index that includes temperature coefficients,line sensitivity,power supply rejection ratio,power consumption and noise.This proposed design of chip uses the cadence-virtuoso for circuit design,pre-simulation,layout design,post-simulation,and uses TSMC₀.18?m technology to make fabrication,and at last the design of the PCB board,the bonding of the chip,and the soldering of the components required for testing are completed.The final test results show that the proposed low-power CMOS voltage reference with current load capability has an output voltage of 143 mV at 0.5-1.8 V and a maximum load current of 300 ?A.The actual circuit function measurement verifies that the sub-threshold CMOS voltage reference of this design has the current loading capability while satisfying the basic performance index of the traditional CMOS voltage reference,achieving the design goal of a low power CMOS voltage reference that does not vary with temperature,supply voltage,and load current.