摘要
介绍了一种改进的LC振荡器设计方法.谐振回路采用非对称电容结构,与常见的振荡器结构相比,经改进后的电路结构可以获得更好的相位噪声.基于0.35μmCMOS工艺,设计了一种采用补偿Colpitts振荡器电路结构实现的差分LC压控振荡器,工作电压为2.5V.经仿真证明,在设计中通过调整非对称电容谐振回路中的电容值,可以获得最优的相位噪声.
This paper introduces the design method of LC oscillators with an asymmetric capacitance tank structure. Better phase noise performance than the conventional differential LC oscillator is achieved. In this way, a complementary-Colpitts differential voltage controlled oscillator(VCO) is designed based on 0.35μm CMOS technology with a 2.5V supply. Simulation results show that the best phase noise is obtained by adjusting the capacitance of the asymmetric capacitance tank structure.