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

作　　者：赵俊杰[1] 顾洺潇 徐宁[1] 钟国强 周泽钊 常玉春[1] ZHAO Junjie;GU Mingxiao;XU Ning;ZHONG Guoqiang;ZHOU Zezhao;CHANG Yuchun(Dalian University of Technology,Dalian,Liaoning 116620,P.R.China)

机构地区：[1]大连理工大学,辽宁大连116620

出　　处：《微电子学》2024年第1期66-72,共7页Microelectronics

基　　金：大连市科学技术局基金项目(2020RT01);2022年产业基础再造和制造业高质量发展专项(TC220A04A-49)。

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48.4μW,启动时间小于15μs。在-40~125℃温度范围内,振荡频率变化率小于±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。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 PTAT 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 48.4μW.The stable time is less than 15μs.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 

分 类 号：TN432[电子电信—微电子学与固体电子学]