Described is an apparatus comprising a first circuitry, a second circuitry, a first capacitor array, and a second capacitor array. The first circuitry may have an oscillator. The first capacitor array may have a set of first capacitors to tune the oscillator. The second capacitor array may have a second capacitor to tune the oscillator. A capacitance of the second capacitor may be greater than an average capacitance of the first capacitors. The second circuitry may be operable to synchronously activate the second capacitor and deactivate a number N of the first capacitors, and to synchronously deactivate the second capacitor and activate the N first capacitors, based on a predetermined sequence.