Resettable Fuses

Resettable fuses, also known as polymeric positive temperature coefficient (PPTC) devices, are a type of circuit protection device that can be used to protect against overcurrent and overvoltage conditions. Unlike traditional fuses, which must be replaced after they have been tripped, resettable fuses can be reset and used again. They work by containing a polymer material that expands when heated, which causes the fuse to open and interrupt the current. When the overcurrent or overvoltage condition is removed, the polymer cools and contracts, allowing the fuse to reset and resume conducting. Resettable fuses are often used in portable electronic devices and other applications where space is limited and the convenience of not having to replace a blown fuse is desirable.