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lumley32

Jul 9, 2012
14
Joined
Jul 9, 2012
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14
more help needed! lol

after finishing my mosfet switches that i put in a different thread i realised that they could with some over current protection, but i want it to be fully automatic!

i found this IC and it will cope with the current, allegro micro-systems ACS756, but i gives a 0-5v output, is there an easy way to use this output to switch of my mosfets? i would like it to latch off until the power is reset. i looked at using a transistor and a divider but when the current got near the limit it would start to switch "half off" as the transistor would not quite saturate.

hear is a digram of what i have so far, the ammeter in there is a replacement of the ACS756.

thanks in advance, any suggestions welcome!
 

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(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Jan 21, 2010
25,510
Joined
Jan 21, 2010
Messages
25,510
I'd suggest that the slow turn-off of your mosfet would pose more risk to it than over-current.

There are a number of mosfet-like devices that incorporate overcurrent and SOA protection as well as integral gate drivers. Perhaps you should consider one of those.

An IR3310S is one option, but there are others (including the one I was actually thinking about, but couldn't find...)
 

lumley32

Jul 9, 2012
14
Joined
Jul 9, 2012
Messages
14
TBH i wasent that worried about protecting the mosfet, more the things its going to power!

that looks like the perfect thing, saves lots of work, i new some one cleverer then me would come to the rescue!

thanks!
 
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