一种用于AC/DC控制器中电压基准源的设计

Design of Voltage Source References for AC/DC Controller

提出了一种新颖的可用于AC/DC控制芯片中的基准电压源电路。此电路以PTAT(proportional to absolutetemperature)电流为偏置电流,利用二极管连接的MOS晶体管迁移率和阈值电压的温度系数可相互补偿的特性,产生与温度无关的栅源电压。该电路结构简单,既无启动电路也无运放,避免了运放失调对基准源的影响,设计采用CSMC0.5μm BCD工艺。仿真结果表明,该基准电压源具有较低的温度系数和高电源电压抑制比,可作为AC/DC控制芯片中迟滞比较器的参考源。

A novel voltage reference is proposed in this paper which can use in AC/DC controller.When a diode-connected MOS transistor is biased with a PTAT（proportional to absolute temperature） current source,the gate-source voltage of such transistor can be temperature independent because of mutual compensation of mobility and threshold voltage temperature variations.The structure of this circuit is very simple： neither start-up circuit nor Op amp.It can avoid the impact of the Op amp offset voltage to the reference.The circuit of design uses CSMC 0.5 μm BCD technology,and the circuit simulations are shown that the voltage references have low temperature coefficient and high PSRR.It can be used as a voltage reference for hysteresis comparator in AC/DC controller.