The microcontroller-based concept was chosen because I wanted to scale the sensor system later to suit other applications. Here is the diagram of my Arduino infrared close proximity sensor ...

New lower priced 18mm and 30mm capacitive proximity sensors have a simple potentiometer sensitivity adjustment. Operating voltages are 10 to 30 VDC; shielded and unshielded versions and NO or NC units ...

Likely applications are button designs and proximity sensing. The kit’s board also includes ... The kit works as a stand-alone unit and as an Arduino-compatible shield. It can be used to add a ...