Patent ID: 7353011

Claim:
A controllable oscillator having an output frequency dependent upon a capacitance amount within an LC tank resonant structure, comprising: a first set of variable capacitor circuits that together provide at least part of the capacitance amount, each variable capacitor circuit having at least one control node configured to receive a control signal that determines at least in part an amount of capacitance contributed by that capacitor circuit to the capacitance amount within the LC tank resonant structure; a second set of variable capacitor circuits that together provide at least part of the capacitance amount, each variable capacitor circuit having at least one control node configured to receive a control signal that determines at least in part an amount of capacitance contributed by that capacitor circuit to the capacitance amount within the LC tank resonant structure; a plurality of first control signals coupled to the first set of variable capacitor circuits to determine an amount of capacitance provided by the first set of variable capacitor circuits; and a plurality of second control signals coupled to the second set of variable capacitor circuits to determine an amount of capacitance provided by the second set of variable capacitor circuits; wherein the first control signals are configured to determine coarse tuning for the controllable oscillator and the second control signals are configured to determine fine tuning for the controllable oscillator.