PROXIMITY SENSING ARRANGEMENT

摘要

This invention includes a proximity sensing arrangement having a square wave oscillator (12); a Schmitt trigger (14-1); a first R-C circuit (16-1) or an integrator coupled between the square wave oscillator (12) and the input of the Schmitt trigger (14-1); and a proximity sensing pad (18) coupled between the resistive and capacitive components of the R-C circuit (16-1).