Fuel injection control device

A fuel injection control device which is provided with an input terminal to which a first pulse signal for driving a liquid fuel injection valve is input and an output terminal from which the first pulse signal is output, and converts the first pulse signal which is input from the input terminal to a second pulse signal for driving a gaseous fuel injection valve, the device comprising:

• a P-channel field-effect transistor interposed in a wiring which connects the input terminal and the output terminal;
• an electronic controller configured to switch between an operation of outputting the first pulse signal from the output terminal and an operation of converting the first pulse signal to the second pulse signal by performing switching control between an ON state and an OFF state of the field-effect transistor;
• a gate drive circuit which maintains the field-effect transistor in the ON state in a case where an operation of the electronic controller is stopped, and
• a protection circuit which is connected between a source and a drain of the field-effect transistor and protects the field-effect transistor when a state of the field-effect transistor is switched,
• where the protection circuit is a Zener diode having an anode which is connected to the drain of the field-effect transistor, and a cathode which is connected to the source of the field-effect transistor.