Patent ID: 7199502

Claim:
A voltage booster circuit ( 1 ) for powering a piezoelectric actuator of an injector, comprising: a first input terminal ( 2 a ) and a second input terminal ( 2 b ) supplied with an input voltage (V i ); a first output terminal ( 3 a ) and a second output terminal ( 3 b ) supplying an output voltage (V o ) greater than the input voltage (V i ), the second input terminal and the second output terminal ( 2 b , 3 b ) being connected to each other; first inductor means ( 5 ) and second inductor means ( 15 ) coupled magnetically and connected in series between the first input terminal ( 2 a ) and the first output terminal ( 3 a ); first capacitor means ( 12 ) connected between the first input terminal ( 2 a ) and the second output terminal ( 2 b ); second capacitor means ( 22 ) connected between the first output terminal ( 3 a ) and the second output terminal ( 3 b ); controlled switching means ( 7 ) connected between the intermediate node ( 15 a ) between the first inductor means ( 5 ) and second inductor means ( 15 ), and the second input terminal ( 2 b ) and the second output terminal ( 3 b ), and which switch between a closed operating state, to permit charging of the first inductor means ( 5 ) by the input voltage (V i ) and an open operating state, to permit transfer of the charge stored in the first inductor means ( 5 ) to the capacitor means ( 22 ) via the second inductor means ( 15 ); a measuring resistor ( 24 ) connected in series to the controlled switching means ( 7 ); a diode 17 connected between the second inductor means ( 15 ) and the first output terminal ( 3 a ), wherein the current of the diode flows from the second inductor means ( 15 ) to the first output terminal ( 3 a ).