题目/Title：伪工作点与超宽带CMOS LC VCO设计
                        Pseudo Operation Point and Design of Ultra Broadband CMOS LC VCO

作者/Author：宁彦卿,王志华,陈弘毅
                        Yanqing Ning,Zhihua Wang,Hongyi Chen

期刊/Journal：电子器件 Journal of Electron Devices

年份/Issue Date：2007.Apr.

卷（期）及页码/Volume（No.）&pages：Vol.30, No.2, pp. 349 - 352

摘要/Abstract：
为了拓宽CMOS LC VCO的频率覆盖范围,很多工作都集中在扩展LC谐振回路中的电容覆盖.但通过对该VCO在调频状态下的分析表明,除了LC乘积的覆盖范围,在改变输出频率时维持交叉耦合MOS管的工作状态稳定也是获得宽带振荡器的条件之一.固定尺寸的交叉耦合MOS管结构不能满足后一个条件.将交叉耦合MOS管结构分为可开关调节的若干段可以有效地解决上述问题.通过VHF超宽频带CMOS LC VCO的具体设计表明,新电路结构可以获得突破性的频率覆盖.
Many effort s have been applied to extend the capacitance coverage in the L C tank for the purpose of ultra broadband CMOS L C VCO design. But the analysis of the tuning situation shows that the varactor change shifts the working stat e of the oscillator. It is discovered that be sides the tuning range of capacitance in the LC tank, another restriction on the broadband CMOS differential VCO is the characteristic of the cross-coupled MOS pair which must be adjusted accompany with the varactor tuning to maintain the oscillation stat e. Dividing the cross-coupled MOSFET pair into switchable part s is a practice and effective method to meet the later condition. The de sign example of a VHF CMOS L C VCO demonstrates that the new schematic can get a breakthrough in the tuning range performance.