Patent ID: 9654003
Date: 2017-05-16
CPC Classifications: H02M,Y02B

Claim:
1. A method of operating a zero voltage transition circuit, comprising: providing a zero voltage transition circuit, comprising an input node receiving an input voltage, an output node outputting an output voltage, a switch node, an output inductor coupled in series between the switch node and the output node, an output capacitor coupled between the output node and a ground potential, a first switch for coupling the input node to the switch node, a second switch for coupling the switch node to the ground potential, a first auxiliary switch for coupling the input node to an auxiliary node, a second auxiliary switch for coupling the auxiliary node to the ground potential, and an auxiliary inductor coupled between the auxiliary node and the switch node; operating the zero voltage transition circuit so that the first switch is open, the second switch is closed, the first auxiliary switch is open, and the second auxiliary switch is open; closing the first auxiliary switch to couple the input voltage to the auxiliary node and to the auxiliary inductor; subsequently, monitoring the current flowing through the second switch and when a current is below a current cutoff threshold, opening the second switch; after a first delay period, opening the first auxiliary switch and subsequently closing the second auxiliary switch; and after a second delay period, closing the first switch.