摘要：A voltage controlled oscillator （VCO） module is designed, which can be used for the third generation mobile communication （3G） system. The circuit is simulated by spectre radio frequency （RF） by TSMC 0.25 μm CMOS process. During the simulation, the performance parameters of the designed VCO are as follows： tuning range 1.804 GHz-2.039 GHz, phase noise - 136.457 dBc/Hz @1 MHz, - 146.045 dBc/Hz@3 MHz, supply voltage 2.5 V, voltage output rate of 0.8 V-2.6 V, power consumption 25 roW. The layout of the related circuit is drawn by the Virtuoso Layout Editor.