A power converter includes a transformer, a primary switch, an auxiliary switch, first and second resonance capacitors, and a secondary side rectification means. A switch mode power supply is formed to use reflected voltage and parasitic capacitance as an energy source for a transformer resonance. The...http://www.google.com/patents/US7764515?utm_source=gb-gplus-sharePatent US7764515 - Two terminals quasi resonant tank circuit
