[Kevint]

I'am building a stepperdriver with an Allegro A3986 driver
and IRFZ24V N-channel powerfet's

Do anyone know how to calculate the series resistors for the gates on these fet's

[epineh]

Unfortunately the 3986 does not perform well in microstepping mode, you may want to try something else, did you read through the 3986 thread ? link :

http://www.cnczone.com/forums/showth...=24699&page=54

In the last couple of pages Mariss from Gecko has offered to program CPLD's to do basically the same job of the 3986, only properly. At five bucks each (though in 100 quantities) it is pretty cheap.

Cheers.

Russell.

[Bostjan M.]

You must buy fet irlz44n (vgs 1-2 v)