A constant power consumption CMOS LC oscillator using improved high-Q active inductor with wide tuning-range

An improved CMOS high-Q active inductor and a constant power consumption oscillator with wide tuning-range are presented. The inductor using one feedback resistor results in a gain to improve the Q-value of the inductor and tune the inductance (L). Based on this inductor, a negative resistance LC-tuned oscillator with constant power consumption and wide tuning-range has been designed. The simulation results show that the improved active inductor can achieve the maximum Q-value of 3500. The power consumption of a constant value around 10 mW exists in the oscillator. This oscillator also depicts a reasonable phase noise performance of -91 dBc/Hz at 600 kHz from 0.8 GHz to 3 GHz range. Furthermore, the deviation of the phase noise is as small as 6 dBc/Hz during this tuning-range.