Peak voltage detection in a differentially driven wireless resonant transmitter

A wireless power circuit comprising:

• (a) a series resonant circuit including a primary capacitor and an inductor coupled in series, the primary capacitor having first and second terminals and the inductor having first and second terminals, a first terminal of the inductor being coupled to a second terminal of the primary capacitor;
• (b) a first half-bridge circuit having a terminal coupled to the first terminal of the capacitor;
• (c) a second half-bridge circuit having a terminal coupled to the second terminal of the inductor;
• (d) a summing circuit having a first summing terminal coupled to the first terminal of the inductor, a second summing terminal coupled to the second terminal of the inductor, and a center node terminal;
• and
• (e) a peek-to-peek voltage detector having an input coupled to the center node terminal of the summing circuit and having a voltage detector output.