Patent ID: 9729064
Date: 2017-08-08
CPC Classifications: H02M,Y02B

Claim:
1. An electrical circuit for providing electrical power for use in powering electronic devices, comprising: a full-wave synchronous rectification circuit electrically coupled to an electrical power source for receiving an alternating current (AC) input power signal from the electrical power source and generating a modified AC power signal, the full-wave synchronous rectification circuit including at least one field effect transistor (FET); a quasi-resonant circuit electrically coupled to the full-wave synchronous rectification circuit for receiving the modified AC power signal and delivering an intermediate power signal, the quasi-resonant circuit including a first switching device that is coupled to the full-wave synchronous rectification circuit, a diode coupled in series between the first switching device and a first inductor, and a first capacitor that is coupled to the first inductor; a power converter circuit electrically coupled to the quasi-resonant circuit through a second capacitor and a second inductor for receiving the intermediate power signal and delivering a direct current (DC) output power signal to an electronic device, the power converter circuit including a transformer and a second switching device coupled to a primary side of the transformer; a Hall Effect sensor coupled to the primary side of the transformer for sensing a magnetic field being generated by the transformer; and a controller configured to: regulate the first and the second switching devices to regulate the transformer to deliver the DC output power signal at a lower voltage level than the AC input power signal; and identify a zero crossing of the transformer as a function of the sensed magnetic field and operate the second switching device to deliver input power to the transformer near the identified transformer zero crossing.