Device for circuit board power surge protection such as protection of telecommunication line cards from lightning and power cross conditions

摘要

A device for line card lightning and power fault protection includes a heat generating fusible resistive element connected to two electrical terminals using a controlled-melting temperature solder. The resistive element has enough thermal mass to withstand low level overcurrent conditions. The electrical terminal configuration and material are designed to thermally isolate the resistor. A spring tensioning device is included to aid in circuit disconnect when sufficient overcurrent exists to melt the resistor-to-terminal solder. The entire assembly is housed in a high temperature insulating plastic enclosure which permits installation using surface mount technology.