基于可变电容反馈技术的宽带VCO设计

Design of a Wide-tuning-range VCO Based on Variable Capacitive Feedback Technology

该文提出了一种用于展宽Colpitts压控振荡器(VCO)调谐范围(T R)的技术。为了实现宽调谐范围,采用一种可变电容反馈技术,该技术同时可得到优于传统Colpitts VCO的相位噪声。且该结构采用动态正向衬底自偏技术,以实现VCO较低功耗、易于起振的特性。基于90 nm CMOS工艺,设计了一款VCO,其相位噪声为-101.9 dBc/Hz@1 MHz,调谐范围为28.1%,考虑调谐范围的品质因数可达-192.2 dBc/Hz。芯片在1 V电压供电下,消耗了5.8 mW,芯片面积为0.45 mm^2。

In this paper,we propose a technique to extend the tuning range(T R)of Colpitts voltage-controlled oscillators(VCOs).To achieve a wide tuning range,we use variable capacitive feedback technology to extend the tuning range while achieving lower phase noise than that of the conventional Colpitts VCOs.In addition,the structure benefits from the dynamic forward-body self-biased technique to reduce the power consumption and facilitate the start-up condition.Based on a 90 nm CMOS technology,a VCO is designed.The VCO achieves a phase noise of-101.9 dBc/Hz at 1 MHz offset,the T R of 28.1%,and the quality factor of-192.2 dBc/Hz considering the tuning range.The chip consumes 5.8 mW of power at 1 V voltage and occupies a 0.45 mm^2 of area.