DC-DC boost converter for driving a capacitive load

Claim 1

A DC-DC boost converter for directly driving a capacitive load, comprising an energy storing inductor, at least a charge switch of the inductor, at least a discharge switch of the inductor toward an output node connected to a terminal of said capacitive load, having a second terminal connected to ground, characterized by comprising a first switch connected between a first terminal of the inductor and a supply rail; a second switch connected between the inductor and ground; a first discharge path between said first terminal of the inductor and said output node, comprising a first diode and a second switch, functionally connected in series; a second discharge path between said second terminal of the inductor and said output node, comprising a second diode and a fourth switch, functionally connected in series; said third and fourth switches being driven in phase opposition at a first control frequency and said first and second switches being driven in phase opposition at a second switching frequency, essentially higher than said first frequency, respectively during a semiperiod of closure of said third switch and during a semiperiod of colosure of said fourth switch.