There are several good reasons to employ a resettable PTC fuse in a circuit design but by and far the best reason is of course that the component automatically "resets" itself after it has acted to open a faulted circuit.
The device has all of the benefits of a fuse (protecting against both short-circuits and overloads) without the downside of having to replace the part once it’s opened one time.
One of the downsides of a resettable PTC fuse has been it relatively narrow usable temperature range especially in non-controlled environments such as automotive applications.
OptiFuse’s new high-temperature resettable fuses have all but eliminated this persistent problem. The new OptiReset RS16HT and RS30HT now have an operating temperature range of -40° C to +125° C (-40° F to +257° F) allowing the fuse to perform in the most harsh of environments (most resettable fuses are only rated to 80° C / 146° F).
The new high temperature resettable fuses have a wide current range of 500mA to 15A at voltages of 16 VDC (the 500mA, 700mA and 1A fuses have a voltage rating of 30 VDC).
The OptiFuse parts cross to the Raychem Tyco RHEF series and the Bourns MF-RHT series. At this time, it doesn’t appear that Littelfuse has a high temperature resettable fuse.
Unfortunately the data sheet for this part won’t be available until later this week on the OptiFuse website.
Not every application has the need for a high-temperature resettable fuse. However, in those situations where temperatures can be extreme, at least now you know that you have a solution to your problem.
Thank you very much for supporting OptiFuse where we hope to provide you a new solutions to old problems.