A 1.5–3.0GHz wideband VCO with low gain variation

摘要

A wideband LC Voltage Control Oscillator (VCO) implemented on SMIC 65nm CMOS process is presented. The proposed VCO has a low gain variation by using the improved capacitor bank technology. In order to reduce the phase noise caused by the tail current and make the wave form more symmetry, a complementary structure without the tail current is adopted. The testing results show that the VCO has the tuning range of 66.7% from 1.511GHz to 3.057GHz; the gain variation is 49.5%. The phase noise of the output ranges from −115.1dBc/Hz to −120.3dBc/Hz at 1 MHz offset. The power dissipation is 1.02mW under 1.2V power supply. The whole layout occupies 0.58×0.67 mm².