一种基于频差自校准的高精度RC振荡器
A High Precision RC Oscillator with Self-Calibration Based on Frequency Offset
赵俊杰 1顾洺潇 1徐宁 1钟国强 1周泽钊 1常玉春1
作者信息
摘要
提出了一种基于频差自校准的高精度RC振荡器.通过对PTAT高频环形振荡器时钟计数,得到RC振荡器和参考时钟的计数偏差.数字自校准电路通过电阻阵列校准参考电压,减小计数偏差,进而得到稳定的振荡频率.参考时钟仅在工作前校准,实际工作中不需要额外的参考时钟.该RC振荡器采用CSMC 0.18μm工艺,工作电压为1.8 V.仿真结果表明,该电路可以产生2 MHz的稳定振荡频率,整个系统的功耗为48.4 μW,启动时间小于15 μs.在-40～125 ℃温度范围内,振荡频率变化率小于士0.2％.在1.70～1.98 V供电电压范围内,振荡频率变化率小于±0.25％/V.
Abstract
A high precision RC oscillator with self-calibration based on frequency offset was proposed.The count offset between RC oscillator and reference clock was obtained by counting the PT AT high frequency ring oscillator.Further,the oscillator was stable by introducing a digital self-calibration circuit with the reduce of the count offset,which was derived from calibrating the reference voltage through a resistance array.The reference clock was only used on time during calibration and was not required in practical work.The proposed RC oscillator was fabricated in 0.18-μm CMOS process with a supply voltage of 1.8 V.The simulation results show that the circuit can generate a stable frequency of 2 MHz,and the power consumption of the entire system is 48.4 μW.The stable time is less than 15 μs.The frequency variation is less than±0.2％in the temperature range of-40 ℃-125 ℃.The frequency variation is less than±0.25％/V within the power supply voltage range of 1.70-1.98 V.
关键词
RC振荡器/自校准/频差/PTAT环形振荡器Key words
RC oscillator/self-calibration/frequency offset/PT AT ring oscillator引用本文复制引用
基金项目
大连市科技局项目(2020RT01)
产业基础再造和制造业高质量发展专项(2022)(TC220A04A-49)
出版年
2024
NETL
NSTL
万方数据