A CMOS 2.45-GHz ring oscillator with temperature compensation

摘要

This paper presents a 2.45-GHz CMOS ring voltage-controlled oscillator (VCO) with a temperature compensation of the oscillation frequency. This compensation is achieved thanks to a biasing current proportional to absolute temperature (PTAT). This method allows to achieve temperature coefficient as low as 73ppm/ ?° C in ??40 ?° C to 120 ?° C temperature range while saving phase-noise performance as well as power consumption of the oscillator. A detailed study of the all-CMOS proposed structure is performed. Simulation results obtained with 0.28-??m STMicroelectronics CMOS technology are presented.