MOTOR DRIVE CIRCUITRY

摘要

A motor drive circuit comprises a positive and a negative supply rail for connection to a battery (104) a motor drive circuit comprising a plurality of motor drive sub circuits 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 comprising 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.