In certain embodiments, a proximity sensor includes a sensing element, an oscillator connected to the sensing element, and control circuitry connected to the oscillator. The sensing element has a capacitance to ground that is variable as a function of the proximity of an object to the sensing element. The oscillator includes a capacitor. The control circuitry is configured to supply an excitation to the oscillator and a charge to the sensing element, and to measure the resonant frequency of the oscillator. The control circuitry provides a signal indicative of the proximity of the object to the sensing element.