一种基于变容管偏置的温度补偿 LC 振荡器

文章介绍一种用于在宽温度范围内产生稳定时钟信号的温度补偿振荡器。该振荡器基于温度对控制电压的影响改变偏置变容管的容值，补偿因温度变化引起的振荡器频率变化，使整个振荡器的温度系数（temperature coefficient，TC）为0。另外，在通过分频产生几十兆赫兹频率的同时，振荡器的相位噪声性能得到进一步优化。该文在SMIC 180 nm CMOS工艺下完成整体电路的设计与仿真。后仿真结果显示，在1.8 V电源下整体功耗为7.12 mW，中心振荡频率2.400 2 GHz处的频率漂移可达到 $ 8.68 \times 10^{-6} \ ^{\circ}C^{-1} $，经过分频后得到的30 MHz信号在10 kHz偏移下的相位噪声大小为-112.923 dBc/Hz。

This paper introduces a temperature compensated oscillator for generating stable clock signals over a wide temperature range. The oscillator compensates the oscillator frequency change due to temperature change by changing the capacitance of the bias varactor based on the effect of temperature on the control voltage, so that the temperature coefficient (TC) of the whole oscillator is zero. In addition, the phase noise of the oscillator is greatly optimized while generating several tens of megahertz frequencies by frequency division. The overall circuit was designed and simulated in SMIC 180 nm CMOS process. The post-simulation results show that the overall power consumption at 1.8 V is 7.12 mW, the frequency drift at the center oscillation frequency of 2.4002 GHz can reach $ 8.68 \times 10^{-6} $ $ ^{\circ} $C $ ^{-1} $, and the phase noise magnitude of the 30 MHz signal obtained after frequency division is -112.923 dBc/Hz at a 10 kHz offset.