Driving control device of brushless motor

A driving control device of a brushless motor comprising:

• an inverter circuit having:
• First arm-side switching elements that are connected between respective phases of respective armature coils of the brushless motor and one terminal of a power supply;
• and second arm-side switching elements that are connected between respective phases of the respective armature coils and the other terminal of the power supply, and a control unit, wherein when electric power from the power supply is not detected, a short-circuit braking according to a short-circuit breaking signal is performed to brake the brushless motor, and wherein, in the short-circuit braking, the control unit outputs a signal of turning off all the first arm-side switching elements and outputs a signal of controlling at least one of the second arm-side switching elements to perform a switching operation, in which the at least one of the second arm-side switching elements is repeatedly switched, and turning on the other second arm-side switching elements.