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Topic: Pulsing a coil (<10A, few millisec) (Read 1 time) previous topic - next topic


I received a PM from "MChus", asking about the schematic & code. Really, it is that simple, as described in the previous post. Well, being lazy I did buy 3 of these from sparkfun, as it was very convenient with the screw terminals for my prototype. And another 10 of the  RFP30N06LE for the actual machine. Note the 10K resistor making sure gate is off when the Arduino is unpowered. I'll add a flyback diode accross the coil on the next circuit to protect the MOSFET.

I have slightly moved away from the orginal spec. My coils are used for mechanical actuator and to get a fast/firm enough pull I am now using 24V and thus using more than 10A. It required a beefy powersupply, too. This is well within the MOSFET spec, but too high for the coils, but as I pulse them shortly with a dutycycle well below 20% I suspect I am safe. Well, no smoke yet :)

The code is as simple. digitalWrite on and off as any LED blink example :) I do not use delay() but timers as outlined here and I use the microseconds() for better resolution.

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