一种高稳定性的振荡电路

文中设计了一种高稳定性的振荡电路,其主要由电流模带隙基准,电压比较器和电容充放电电路构成。带隙基准产生三组基准电压,一组用于生成振荡电路中电容的充电电流,一组作为比较器的判决门限,另一组用于产生振荡部分的工作电压。电压比较器门限和充电电流的大小控制振荡电路的振荡频率。整个电路采用SMIC 0.18μm CMOS工艺实现。通过Hspice仿真,在-20℃~70℃、1.8V~3.8V工作范围内振荡精度在1%左右。

A High Stability Oscillation Circuit

This paper introduces the design of a high stability oscillation circuit, which mainly consists of the band-gap reference, the voltage comparator and the capacitor charge and discharge circuit. There are three reference voltage generated by the band-gap reference, one is used to generate the circuit of the capacitor charging current, one is used as the comparator threshold, another is used to generate the working voltage of the oscillating portion. The comparator＇s threshold and the charging current control the oscillation frequency of the oscillation circuit. The current is implemented in SMIC 0.18μm CMOS process. Simulation shows the Oscillation accuracy is around 1% in the range from -20℃ to 70℃ and 1.8V to 3.8V.