Resettable fuse

Resettable fuses - PolySwitch devices

A resettable fuse or polymeric positive temperature coefficient device (PPTC) is a passive electronic component used to protect against overcurrent faults in electronic circuits. The device is also known as a multifuse or polyfuse or polyswitch. They are similar in function to PTC thermistors in certain situations but operate on mechanical changes instead of charge carrier effects in semiconductors. These devices were first discovered and described by Gerald Pearson at Bell Labs in 1939 and described in US patent #2,258,958.[1]

  1. ^ U.S. Patent 2258958.: "Conductive device", filed 13 Jul 1939, retrieved 7 mar 2017.