than would occur with higher current levels since power consumption is directly related to the square of the current such a current reduction provides a drastic reduction in power thus the two phase current control not only affords rapid opening and closing of the fuel injection valve but also achieves a substantial savings in power consumption and improved thermal conditions in the illustrated embodiment the pulse width modulator 226 is a circuit which operates at a relatively high frequency to produce an output voltage having a controllable or modulated level for powering the solenoid 182 more particularly the pulse width modulator 226 controls the duty cycle of a control switch 227 to cause a current flow through the solenoid 182 and the sensing resistor 220 sensed through the input resistor 221 to match the level of the drive current demanded by the complex input pulse 219 it will be appreciated that although other drive schemes and modulation means can be employed the pulse width modulation as described above is presently preferred the pulse width modulation applied by the circuit 226 is one possible mechanism for controlling the current through the solenoid 182 to insure consistent valve operation from cycle to cycle thus other schemes capable of controlling current flow in the solenoid 182 which can rapidly and repeatedly open and close the fuel injection valve might also be appropriate as will be appreciated from the description that follows several important features of a preferred embodiment of the present invention are achieved by a driver switch 230 which is in series circuit relationship with a driving power supply 225 a.