Patent ID: 7548436
Filing Date: 2009-06-16
Classification: H02M,Y02B

Abstract:
1. A power converter adapted to be connected electrically to an input power source and an external load, and adapted for receiving a driving signal that has high and low signal levels, said power converter comprising: a main switch operable in one of a conducting state and a non-conducting state according to the driving signal; a main transformer including a primary coil adapted to be connected between the input power source and said main switch for receiving an input power supplied by the input power source when said main switch operates in the conducting state, and a secondary coil coupled electromagnetically to said primary coil; a switching circuit adapted to be connected electrically between said secondary coil of said main transformer and the external load for transferring energy from said main transformer to the external load, said switching circuit outputting a sync signal that has high and low signal levels, and including a circuit switch that is operable in one of a conducting state and a non-conducting state; and a driving circuit including wherein transition of the driving signal from the high signal level to the low signal level causes said third switch to operate in the off state and the sync signal to transition from the high signal level to the low signal level, such that said first switch operates in the off state and permits operation of said fourth switch in the on state, and such that the switching signal transitions from a low signal level to a high signal level with a dead time existing between a falling edge of the sync signal and a rising edge of the switching signal; wherein transition of the driving signal from the low signal level to the high signal level causes said third switch to operate in the on state and the sync signal to transition from the low signal level to the high signal level, such that said fourth switch is operated in the off state, and such that the switching signal transitions from the high signal level to the low signal level with a dead time existing between a falling edge of the switching signal and a rising edge of the sync signal.