Abstract: A high-performance and highly reliable load driving device is provided that can quickly charge an ESD protection capacitor even at the time of load disconnection and complete all diagnoses of the driving system driver within a required time in a load driving device including a diagnosis circuit of a driving system driver and an ESD protection capacitor. A load driving device includes a load; a first switch element connected to the load and configured to control driving of the load; an ESD protection capacitor connected between the load and the first switch element; a charging circuit connected between the load and the first switch element and configured to charge the ESD protection capacitor; and a second switch element connected between the ESD protection capacitor and the charging circuit.

Abstract: A drive circuit is controlled when power is interrupted. When power is turned off, a main power supply is switched to a sub-power supply, and a residual charge of a step-up circuit is lowered to a drive voltage of a drive circuit using a step-down circuit is used as the sub-power supply.

Abstract: A drive circuit is controlled when power is interrupted. When power is turned off, a main power supply is switched to a sub-power supply, and a residual charge of a step-up circuit is lowered to a drive voltage of a drive circuit using a step-down circuit is used as the sub-power supply.