FUEL INJECTION DEVICE OF INTERNAL COMBUSTION ENGINE

摘要

A step-down circuit is connected to an output of a step-up circuit that steps up a battery voltage, and an output of the step-down circuit is connected to a power supply input terminal of a CPU via an FET. The step-down circuit is normally maintained in an inactive state and, in response to an ignition switch being turned off, the CPU causes the step-down circuit to actuate and a stepped-down voltage (equal to a stabilized voltage) is output from the step-down circuit. The stepped-down voltage is further stepped down to a CPU power supply voltage, and the CPU power supply voltage is supplied to the power supply input terminal of the CPU. This allows the residual charge of the step-up circuit to be dissipated by the step-down circuit and the CPU.

主权项

1. A fuel injection device of an internal combustion engine, the device comprising:
a fuel injection valve that injects fuel directly into a combustion chamber of the internal combustion engine; a control computing unit that controls operation of the fuel injection valve; a battery; a step-up circuit that is connected to the battery and steps up a battery output voltage to output a stepped-up voltage; and a discharging circuit that is connected to an output side of the step-up circuit and causes residual charge in the step-up circuit to be rapidly dissipated when an ignition switch for turning on and off a power supply voltage supplied to the control computing unit is turned off.