Abstract: A motor drive circuit includes a positive and a negative supply rail for connection to a battery (104), a motor drive circuit including a plurality of motor drive subcircuits which each selectively permit current to flow into or out of a respective phase of a multi-phase motor (101) in response to control signals from a motor control circuit, and a switching means including at least one switch which is in series with a respective phase of the motor which is normally closed to permit the flow of current to and from the subcircuit to the respective motor phase. A fault signal detecting means (160) detects at least one fault condition and, in the event of a fault condition being detected, causes the at least one switch to open. A snubber circuit (150) is associated with the motor and is arranged so that following the opening of the switch, energy stored in the motor windings is diverted away from the switching means through the snubber circuit to the battery.

Abstract: A motor drive circuit includes a positive and a negative supply rail for connection to a battery (104) a motor drive circuit including a plurality of motor drive subcircuits which each selectively permit current to flow into or out of a respective phase of a multi-phase motor (101) in response to control signals from a motor control circuit, and a switching means including at least one switch which is in series with a respective phase of the motor which is normally closed to permit the flow of current to and from the subcircuit to the respective motor phase. A fault signal detecting means (160) detects at least one fault condition and in the event of a fault condition being detected, causes the at least one switch to open. A snubber circuit (150) is associated with the motor and is arranged so that following the opening of the switch, energy stored in the motor windings is diverted away from the switching means through the snubber circuit to the battery.