On Thu, 05 Feb 2015 09:49:52 -0800, Jeff Liebermann
wrote:

One could also use a PTC inrush current limiter as a temporary fuse.
Too much current and it gets hot and goes "open". The problem is
selecting the right combination of on-resistance and trip current.
http://en.wikipedia.org/wiki/Resettable_fuse

Argh, that's wrong. Clarifying my muddle:

An inrush current limiter is an NTC (negative temperature coefficient)
device. When cold, it has a high resistance. As current heats up the
device, the resistance goes down.
http://en.wikipedia.org/wiki/Inrush_current_limiter

An electronic fuse is a PTC (positive temperature coefficient) device.
When cold, the resistance is low. When too much current goes through
the device and it becomes hot, the resistance goes up.
http://en.wikipedia.org/wiki/Resettable_fuse

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Jeff Liebermann
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