Resettable Fuses (PTC)

Resettable polymeric PTC fuses (polyfuse, PolySwitch) of RUEF and RUSBF series. On overload they sharply increase resistance and limit current; after cooling they return to the conductive state without replacement. Hold currents 0.05-3 A, voltages 16-60 V. Radial-lead and SMD packages. Filter by hold current Ihold, trip current Itrip, voltage, and package. Used in USB ports, motherboards, controllers, networking gear, and battery modules for short-circuit protection without physical replacement.