一种用于卫星导航接收机的上电复位电路

Power-on-reset Circuit for Global Navigation Satellite System Receiver

利用工作在亚阈值区的带隙基准源和比较器电路提供高精度的比较基准，利用电流可控制的环形振荡器和可编程数字计数电路提供低静态功耗及可编程的上电延时时间，提出了一种适用于卫星导航接收机的高精度上电复位及电源监控电路。采用SMIC 0．18μm CMOS工艺流片验证，测试表明，电路在3．3V电源电压条件下静态电流为10μA，上电复位延时时间为200～400ms，触发电平为3V±2％。

A high precision power on-reset and power supervision circuit is proposed. The ac curate threshold voltage is achieved by a bandgap reference based on subthreshold MOS amplifier and hysteresis comparator. The current controlled ring oscillator and digital counter could reduce the static power consumption and provide programmable reset time. The circuit is simulated and validated by SMIC 0.18 μm CMOS process. The circuit draws 10 μA current from a 3.3 V sup- ply, power on reset delay time is ranged from 200 to 400 millisecond, and the measured threshold voltage is 3 V±2% .