For my project I need to be able to drive several electro magnets (just large hand wound coils). I'm planning on using darlington arrays to sink the current through the coils.
I will also power my arduino pro (from sparkfun) with the 7.2V nicd battery pack.
I know that I need to place a 500uf capacitor across the battery and a diod to stop backflow so that the draw from the coils do not drop the logic supply too far. And I also know that the Arduino pro has a 5v regulator built in, but what I'm worried about is the current.
The question is this. What precautions in general do I need to take when connecting a 7.2V nicd pack (like the kind for remote cars) to the arduino? Do I need a current limiting resistor? I do not want to overheat the regulator. Can I connect it to the JST battery connector on the Arduino Pro's board? I want to make sure that I do this correctly. If you have any experience with this I would greatly appreciate any help.
Thanks in advance.