基于SMIC 28nm工艺实现了一种用于Flash的低功耗高精度的带隙基准电路,在传统电压模结构上采用共源共栅结构提高了各支路偏置电流的精度和PSRR,设计过程中仿真了器件所有corner,温度范围-40~125℃和电源电压±10%的情况.300次Monte Carlo仿真输出电压平均值为1.196 42V,方差为5.011mV,温度系数为7×10-6/℃,总电流仅为264nA,电源电压为1.8V时,最恶劣corner总电流为343nA,低频1kHz电源抑制比为-78dB.该电路中设计了一款新的启动电路,该电路由带负反馈的三支路偏置电路和施密特触发器组成,极大地提高了电路的稳定性,芯片版图面积为105μm×110μm.
Abstract: Based on SMIC 28 rim, a low-power and high-percision bandgap reference voltage for Flash memory is presented in the paper. Cascode is used to improve the percision of the bias current and PSRR. In this circuit design process , all process corner , the rage of temperature is -40-125℃ and power floats+ 10% has been simulated. With three hundreds Monte Carlo, the mean of output voltage is 1. 196 42 V and standard deviation is 5. 011 my, the coefficient is 7 ppm/℃, the total current is 260 nA and When the power is 1.8 V the worse case is 343 nA and the PSRR is --78 dB at 1 kHz. A new startup circuit is presented, with the introduction of Schmitt Trigger and tip- branch, the bandgap shows better stability. The area of layout is 105μm×110μm.