Fet overkill?

[eetoi]

I want to do a fet upgrade, but I really don't like ordering online I went to the RS website, and it seems all they have are IRF510's and are only N-channel (I think). I went to the xmods science, and I read that the FETs used could handle like hundreds of amps, and I am wondering if you really need all that for an xmod (a plasma dash, found elsewhere, draws up to 1.8 amps w/o load.) At digikey the chart said the IRF510's can handle up to 5.6 amps, and that seemed reasonable to me. Here's the question: can I use the IRF510's without any disadvantage other than on-resistance (I'm hoping it's low) on my xmod? I might be using a plasma dash, or maybe even an Auldey panther (faster, I think). And can I get P-channel fets from RS? Why do I need both N and P? Forward and reverse?

[spitty12]

Good question(bump) sorry

[neurokinetik]

Well, those IRF510s don't even handle as much current as a IRF7389. You'd be better off just buying four IRF7389s and doing a 2x2 stack. Cost would be less once you figure in the price of the board and wire that you'd need for the IRF510. Plus you'd need to revise the circuit if you wanted to use all N Channel FETs. The circuit is designed for the complementary N and P channel setup. We don't know this for a fact yet, but the stock XMods FETs may actually handle as much current as the IRF7389, so in other words, the IRF510s will gain you nothing.

A Plasma Dash will fry a FET stack, and also keep in mind that the no-load current represents the absolute lowest current a motor will draw. As soon as you install it in a car, it goes up. Use a big pinion gear, it goes up even more. The first time you try to accelerate with that motor, those IRF510s will pop.