【摘要】 提出了一种基于自偏置尾电流整形的宽带正交压控振荡器(Q-VCO)结构,其输出信号的交流成分和负峰值通过电容和峰值检测器叠加反馈到尾管的栅极作为偏置电压,用来抑制尾电流的噪声和稳定LC-tank的幅度,达到优化相位噪声的目的。在TSMC0.18μm CMOS工艺中,利用该结构设计频率覆盖率为66%,调谐范围为1.55GHz到3.1 GHz的宽带Q-VCO电路时,基于SpectreRF的模拟结果表明:当谐振频率从1.55GHz跳变到3.1 GHz时,最大的幅度改变仅为330mV;在3.1 GHz载波处,1 MHz频偏处的相位噪声为-126.4dBc/Hz,较没有幅度控制改进了2.4dB,且整个调谐频段范围内FoM约为-184。更多还原

【Abstract】 a wideband Q-VCO topology based on self-bias tail current-shaping is proposed,in which the AC component and the negative peak voltage of the Q-VCO’s outputs are fed back to the gate of tail-current transistors as the bias voltage by a capacitor and a peak detector respectively.This topology is designed to improve Q-VCO’ s phase noise by suppressing noise from the tail-current transistor and stabilizing the LC-tank amplitude.A wideband Q-VCO circuit with a tuning range of 66%from 1.55GHz to 3.1GHz is designed using the proposed topology in the TSMC0.18jxm CMOS technology.The SpectreRF based simulation results show that the maximum amplitude variation is only 330mV when the tuning frequency is increased to 3.1 GHz,and the phase noise at the 3.1 GHz carrier frequency and 1MHz frequency offset is- 126.4dBc/Hz,which is 2.4dB better than the case without the LC-tank amplitude control.Moreover,the FoM is about-184 over the whole tuning frequency.更多还原