Low power voltage controlled oscillator (VCO)

An apparatus comprising:

• a tank circuit of a voltage controlled oscillator;
• a pair of transistors, each transistor of the pair of transistors having a gate, drain, and a source, wherein the drain of each transistor of the pair of transistors is coupled to the tank circuit;
• a pair of alternating current (AC) coupling capacitors, wherein the pair of AC coupling capacitors respectively couple the gates of the pair of transistors to the drains of the pair of transistors;
• a bias circuit coupled to the gates of the pair of transistors, the bias circuit to bias the pair of transistors in accordance with a bias voltage such that
• i) the pair of transistors alternatingly turn on during a plurality of peaks of an oscillating signal of the tank circuit, and
• ii) the pair of transistors turn off during a plurality of crossing points of the oscillating signal;
• a feedback loop configured to i) detect a peak oscillating amplitude of the oscillating signal, and ii) adjust the bias voltage of the bias circuit based on the peak oscillating amplitude;
• and
• a supply capacitor coupled to the tank circuit and to the pair of transistors, the supply capacitor to provide current to the voltage controlled oscillator.