基于对称螺旋型电感和差分二极管的2.4GHz CMOS正交输出压控振荡器

提出了一种产生2.4GHz正交本地振荡信号的方法.它将LC-VCO和两级环路振荡器两种结构组合起来以实现正交输出的低相位噪声压控振荡器.LC网络是由在片对称螺旋型电感和差分二极管组成的.详细论述了VCO原理及其噪声性能.该电路已经用0.25μm单层多晶、五层金属N阱CMOS数字工艺制作.测量结果表明:它可以提供正交的本地振荡信号,其振荡频率可以在300MHz的范围内调节,当仅对差分输出振荡信号的一端进行测试时,振荡频率为2.41GHz时,去偏移中心为600kHz时的相位噪声为-104.33dBc/Hz.而且,它能在很低的电源电压下工作,功耗也很低,所以,它在集成收发机中将得到广泛的应用.

A 2.4GHz CMOS Quadrature Voltage-Controlled Oscillator Based on Symmetrical Spiral Inductors and Differential Diodes

A voltage-controlled oscillator (VCO) which can generate 2.4GHz quadrature local oscillating (LO) sig-nals is reported.It combines a LC VCO,realized by on-chip symmetrical spiral inductors and differential diodes,and a two-stage ring VCO.The principle of this VCO is demonstrated and further the phase noise is discussed in detail.The fabrication of prototype is demonstrated using 0.25μm single-poly five-metal N-well salicide CMOS digital process.The reports show that the novel VCO is can generate quadrature LO signals with a tuning range of more than 300MHz as well as the phase noise--104.33dBc/Hz at 600KHz offset at 2.41GHz (when measuring only one port of differential outputs).In addition,this VCO can work in low power supply voltage and dissipate low power,thus it can be used in many integrated transceivers.