PPTC Resettable Fuse Products Yageo PPTC Resettable Fuse Products are available in SMD case sizes 0603 through 2920 and in DIP package types. Polymeric positive temperature coefficient thermistor (PPTC) is also known as a resettable fuse. It has low resistance under normal working status and no impact on the working circuit. The response speed of the PPTC ranges from a few dozen microseconds to a few seconds. It is proportional to the current value. Yageo PPTC Resettable Fuse Products feature a compact design to save board space. They are RoHS compliant, lead free, and halogen free and ideal for use in a range of applications.