无电阻CMOS带隙基准电压源的设计

Design of a CMOS Band-Gap Voltage Reference Without Resistors

设计了一种高准确度无电阻的带隙基准电压源。该电路采用差分结构的电压传输单元来代替电阻,并且没有使用运算放大器,从而避免了运算放大器所带来的高失调和必须补偿的缺陷。电流源采用共源共栅结构,提高了电源抑制比。增加了启动电路,保证电路可以正常工作。在0.6μm CMOS工艺条件下,电路的各项性能指标采用Sm artSp ice进行模拟验证,结果表明有效温度系数可以达到6×10-6/℃,电源电压从3.8 V变化到5.5 V时,输出的基准电压波动不到3 mV。

A high accuracy band-gap reference voltage without resistor is designed. The circuit uses voltage-transfer unit of differential configuration instead of resistors and does not adopt operation amplifier in order to avoid the operation amplifier＇ s defects of high maladjustment and obligatory compensation. The current source adopts cascade structure to improve power supply rejection ration （PSRR）. Add the startup circuit to assure the circuit operating smoothly. The simulation with SmartSpice is carried out using a 0.6 μm CMOS process. The results indicate that the effective temperature coefficient can arrive at 6 × 10-6/℃, the fluctuation of the output reference voltage is less than 3 mV when the power voltage ehanges from 3.8 V to 5.5 V.