Motor drive device and electric power steering device

A motor drive device for driving a motor, the motor drive device comprising:

• an inverter circuit to supply a current supplied from an external power supply to the motor;
• a first switching circuit to switch a current supply path between the external power supply and the inverter circuit to a conducting state and an interrupted state;
• a second switching circuit to switch a current supply path between the inverter circuit and the motor to a conducting state and an interrupted state;
• a current detector to detect a current flowing through the inverter circuit;
• a controller to, in a case in which a current value of the detected current is not within a predetermined range, output an interruption command voltage that commands switching from the conducting state to the interrupted state;
• and
• a switching driver to boost the interruption command voltage input from the controller to output the boosted interruption command voltage to the first switching circuit and the second switching circuit;
• wherein
• a delay circuit is disposed between the second switching circuit and the switching driver to set a timing at which the boosted interruption command voltage is input to the second switching circuit to be later than a timing at which the boosted interruption command voltage is input to the first switching circuit.