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Author Topic: Max amperage  (Read 691 times)
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Hello
What is the max the max amperage the arduino mini 5V pro used? I want to put a Polyswitch before the supply od the arduino in order to protect it.
Thanks
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USB interfaces normally have a 500mA Polyswitch as part of the design. If you want to be safe... use a value less than that.  You need to keep in mind what your peripherals draw,  the AVR chip itself is very low on power consumption (like well below 1mA).
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Quote
(like well below 1mA)
The data sheet says:-
12mA when running at 8MHz and 3.5mA when running at 4MHz
There is also the USB / serial bridge chip, so that pushes it up to 20mA.

This however is way too low for a poly fuse. Those things are very slow to blow and only protect the supply from short circuits, they won't protect the arduino from things like drawing too much current from a pin, putting 12V into the voltage reference pin or trying to power the chip with greater than 5V. All of which are common beginner mistakes.
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The 5V Mini Pro is 16MHz so it'll take more like 25mA.  What is the fuse to protect against?
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