In accordance with an embodiment, an automatic zeroing circuit is provided that includes an automatic zeroing circuit, comprising a first voltage adjustment circuit coupled for receiving an induced voltage and a second voltage adjustment circuit coupled for receiving a common voltage. A comparator having an inverting input terminal coupled to the first voltage adjustment circuit and a noninverting input terminal coupled to the second voltage adjustment circuit. In accordance with another embodiment, a method for automatically zeroing a detection circuit includes receiving a first back electromotive force at a first voltage level and shifting the first back electromotive force from the first voltage level to a second voltage level. A comparator circuit is calibrated and the first back electromotive force is detected.