Patent ID: 8111214

Claim:
A control circuit comprising: a low voltage DC source; a supply circuit including: a converter including at least one converter switching element and arranged to receive a first voltage supplied from the low voltage DC source and to generate a pulsed direct current; and switching elements arranged to define an H-bridge circuit including two parallel limbs that each include a first switching element in series with a second switching element and a node between the first and second switching elements; a capacitive load connected between the respective nodes of the two parallel limbs and arranged to be charged to a voltage which is higher than that of the low voltage DC source by receiving the pulsed direct current from the H-bridge circuit; and a discharge circuit arranged to receive a high voltage discharge current from the capacitive load and to generate a second voltage that is higher than the first voltage at least during charging of the capacitive load; wherein the second voltage is used to drive the switching elements of the H-bridge circuit and the at least one converter switching element.