Abstract: A method and a voltage-controlled oscillator provide an output signal with a frequency within one of a plurality of frequency bands, while reducing or eliminating temperature-induced band-switching or other drifts in operating frequency. The band-switching is reduced or eliminated by providing a circuit that adjusts a tuning sensitivity according to a calibration performed under test conditions. For example, such a voltage-controlled oscillator may include (a) a digitally controlled variable current source for providing a first control current to select one of the frequency bands for the voltage-controlled oscillator; (b) a variable transconductance circuit providing a second control current to compensate a variation in operating frequency; and (c) a control circuit for varying the frequency of the output signal in accordance with the first and second control signals.

Abstract: A method and a voltage-controlled oscillator provide an output signal with a frequency within one of a plurality of frequency bands, while reducing or eliminating temperature-induced band-switching or other drifts in operating frequency. The band-switching is reduced or eliminated by providing a circuit that adjusts a tuning sensitivity according to a calibration performed under test conditions. For example, such a voltage-controlled oscillator may include (a) a digitally controlled variable current source for providing a first control current to select one of the frequency bands for the voltage-controlled oscillator; (b) a variable transconductance circuit providing a second control current to compensate a variation in operating frequency; and (c) a control circuit for varying the frequency of the output signal in accordance with the first and second control signals.