Patent ID: 8783230

Claim:
An engine control unit for an internal-combustion engine driving a fuel injection valve electromagnetically to provide fuel injection multiple number of times per operation cycle to a combustion chamber of the internal-combustion engine, the engine control unit comprising: a microcomputer outputting a valve open time for opening the fuel injection valve and a injection time for injecting the fuel injection valve; a booster circuit that boosts the voltage of the battery to generate a boost voltage for the engine control unit; a voltage driver which controls the supply of an Ipeak current generated by the boost voltage, and an Ihold 1 current generated by the boost voltage or the battery voltage smaller than the Ipeak current to the fuel injection valve according to the valve opening time, and controls the supply of an Ihold 2 current generated by the battery voltage smaller than the Ihold 1 current to the fuel injection valve according to the fuel injection; time, wherein the Ipeak current and the Ihold 1 current are predetermined to open the fuel injection valve and the Ihold 1 current is provided to complete the valve open action of the fuel injection valve, and the Ihold 2 current is predetermined to hold the fuel injection valve open, and the valve open time is extended to control the providing current to the fuel injection valve to reach to the Ipeak current when the boost voltage of the booster circuit is below a predefined normal voltage V 0 .