Patent ID: 7336018

Claim:
A circuit configuration for charging and discharging a plurality of capacitive actuators in a fuel injector configuration in an internal combustion engine of a vehicle, the circuit configuration comprising: an energy source; a charge capacitor connected to and charged by said energy source to a charge voltage predefined in relation to a vehicle ground, the charge voltage being selected as negative in relation to the vehicle ground; charge circuits each for charging one of the capacitive actuators, said charge circuits each connected parallel to said charge capacitor, said charge circuits having a common charge circuit section containing a choke and a plurality of charge circuit sections configured parallel to each other and corresponding to a number of the capacitive actuators, said charge circuit sections each having a selector/charge switch, in each of said charge circuits one of the capacitive actuators is disposed in a series circuit with said choke and said selector/charge switch, each of said charge circuit sections having said selector/charge switch connected in series to one of the capacitive actuators; discharge circuits each for discharging one of the capacitive actuators, said discharge circuits having a common discharge circuit section containing a discharge switch and a plurality of discharge circuit sections configured parallel to each other and corresponding to the number of the capacitive actuators, said discharge circuits each connected parallel to a series circuit formed by said choke and one of the capacitive actuators, each of said discharge circuit sections having a decoupling diode; and a sensing resistor for measuring current flowing via the capacitive actuators during charging and discharging, said sensing resistor disposed in a series circuit with said choke such that said choke forms part of said common charge circuit section and said common discharge circuit section, said sensing resistor having a terminal connected to the vehicle ground.