HIGH-SIDE DRIVE CIRCUIT, MOTOR DRIVE DEVICE, AND DC-DC CONVERTER

摘要

PROBLEM TO BE SOLVED: To provide a high-side drive circuit that allows preventing a useless current from flowing when a high-side switch changes from an on state to an off state.SOLUTION: A high-side drive circuit 1 includes an NMOS transistor NM1 that is a high-side switch connected between a power-supply terminal VM and an output terminal OUT. A PMOS transistor PM1 is connected between a high-voltage power-supply terminal VH having a higher voltage than that of the power-supply terminal VM and a gate terminal of the NMOS transistor NM1, and its conduction is controlled by a control signal S1. A PMOS transistor PM2 constitutes a first feedback path between the output terminal OUT and the gate terminal of the NMOS transistor NM1. NMOS transistors NM2 and NM3 constitute a second feedback path between the output terminal OUT and the gate terminal of the NMOS transistor NM1, and their conduction is controlled by control signals S2 and S3. A feedback control section 11 controls conduction of the first feedback path and the second feedback path.