Raychem Polyswitch makes a resetable fuse that is SMT and small in size.
While not as clever as a " home-made" solution, it is less risky and
more predictable. 


       At 07:56 AM 10/1/96 -0500, you wrote:
>   I searched the ipc.org archives but didn't come up with any relevant
>hints on how to design a fusible link into a circuit board.  I want to
>run a 50 mil trace but neck it down to some value for about 200 mils so
>that if overcurrent is applied I'll know where it'll blow.  This would
>be such a rare occasion that a fuse is not warranted nor practical due
>to high voltage, >1000.
>   Does anyone have any idea on how to tackle this?  What calculations
>should I use to determine when the neck down will fry?  The IPC curves
>are very conservative in our experience.  I want it to blow not glow?
>:-)  Remember that the nearby 50 mil trace will heatsink the neck down
>to some extent.
>   Thanks for any input.  Any replies direct to me will be concatenated
>and disseminated over TechNet unless otherwise requested.
>
>George Uptain - Schlumberger Well Services
>512-331-3183
>Austin, Texas
>
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