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

摘要

A proximity detector for sensing a magnetic field includes a magnetic-field-to-voltage transducer for generating a signal voltage V_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_sig and for providing an output signal voltage V_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_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.