Patent Number: 6,297,627

Title: Detection of passing magnetic articles with a peak-to-peak percentage threshold detector having a forcing circuit and automatic gain control

Abstract: A proximity detector for sensing a magnetic field includes a magnetic-field-to-voltage transducer for generating a signal voltage V.sub.sig that is proportional to the magnetic field, a peak-to-peak percentage threshold detector coupled to the magnetic-field-to-voltage transducer to receive the signal voltage V.sub.sig and for providing an output signal voltage V.sub.out and a forcing circuit coupled to the peak-to-peak percentage threshold detector for forcing and maintaining the value of the output signal voltage V.sub.out at a predetermined value during an initial startup interval of the proximity detector. The proximity detector may further include an automatic gain control circuit coupled to the forcing circuit to provide a proximity detector capable of operating in a peak-to-peak percentage threshold detector mode with automatic gain control.

Inventors: Towne; Jay M. (Newbury, NH), Vig; Ravi (Bow, NH), Scheller; P. Karl (Rochester, NH)

Assignee: Allegro Microsystems, Inc.

International Classification: F02P 17/00 (20060101); F02P 17/02 (20060101); G01P 3/42 (20060101); G01B 7/30 (20060101); G01B 7/14 (20060101); G01P 3/48 (20060101); G01P 3/489 (20060101); H03G 1/00 (20060101); G01P 003/48 (); G01P 003/489 (); G01B 007/14 ()

Expiration Date: 10/02/2018