DETECTION METHOD AND STRUCTURE WITH RFI CHOKE FOR BRUSH DC MOTOR

摘要

A brush type DC motor (10) having an armature (15) and positive and negative power leads is provided. The motor includes an RFI choke (12) as a transformer in series with at least one of the positive and negative power leads to amplify current such that rotation of the armature (15) can be detected based on monitoring a voltage relating to the amplified current. Conditioning circuitry (14) is constructed and arranged to condition the voltage for detecting rotation of the armature.