Reed Switch
The Reed Click Board™ features a magnetic reed switch with unique switching capability. It comprises of two ferromagnetic nickel-iron wires and a glass capsule. Until a magnetic field is applied, the two contacts (one magnetic north pole, one south) remain separate. On application of the magnetic field, the contacts get shut and activate the switch. On removing the magnetic field, the contacts open up again.
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SMD Jumper
Reed Click Board™ is used with a 3.3V or 5V power supply. A zero-ohm SMD jumper allows user to select a power supply between the two.