What would be a resonable simple circuit that could take the Arduino outputpin and deliver a 5 maybe up to 10A current to a coil (electromagnet)?
I've tried with a MOSFET (FQP30N06 N-channel, 30A, 60V 0,04mOhm Rds) but it seems only to deliver 2A - somewhere I loose power. The coil has between 2 and 3 Ohms resistance (I have several) I put an extra switch transistor in front to give a higher voltage to the gate (it needs 10V for fully on, if I understand the spec sheet rightly)
It isn't the power supply, that is a large labsupply, and when connecting the coil directly to it, it cheerfully supplies 2-4-8A (whatever I set it's current limit to) and can pulse it, too (I just briefly "clap" the wires) sparks fly and I can see the "magnetic pulse" by the way the pliers jump towards the coil 8)
In an ideal world, the specifications are :
- Input signal is from the Arduino.
- Power Supply is 12 or 24V (well, to push 8A through 3 Ohms I need 24V) or maybe even more ...
- The pulse will be a few milliseconds long, maybe as short as 0.1, so the "rise time" of the coil current should be in the order of ten microseconds. Of course, I dont know the inductance.. so it will just be what it is, but the circuit shoud deliver "full power" as fast as possible
- The duty cycle will be of the order 20% at peak times (lasting a few seconds) and down to 1% otherwise, so some overloading is allowed (The coil can only take 2A continuous so at 10A I must keep below 20%)
Thanks in advance