Patent ID: 6825641
Filing Date: 2004-11-30
Classification: H02M

Abstract:
A switched-mode DC-DC converter for converting an unregulated input voltage into at least one regulated output voltage, comprising:an inductor; a capacitor coupled to the inductor; a rectifier coupled to the inductor and capacitor; a controllable electrical switch coupled to the inductor the capacitor and the rectifier, the electrical switch including a first FET having gate, drain and source terminals, and having a first switching speed, and a second FET having a gate terminal, a drain terminal coupled to the drain terminal of the first FET, a source terminal coupled to the source terminal of the second FET, a switching time of the first FET being less than a switching time of the second FET; and a controller operating to turn the first FET on before the second FET during a turn on transition of the controllable electrical switch, and to turn the first FET off after the second FET during a turn off transition of the controllable electrical switch.