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I'm looking for a MOSFET which can be controlled by an Arduino at 5V, and which can switch power on/off to a Raspberry Pi and peripherals (also 5V) that will peak around 3A of current. It's a battery-powered project, so minimal wasted energy is ideal, and there is no need to rapidly switch the power supply on/off. A cursory search for logic level MOSFETS on AliExpress turned up IRFB3006PBF. Its low Rds(on) of 2.5 mΩ seemed pretty good, and it seemed to tick all the right boxes, with a max Vgs of 4V.

The max Vgs means it would definitely be all the way on at 5V GS voltage, right?

Would this work, or have I missed something important that would make this unsuitable?

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    \$\begingroup\$ Beware that aliexpress/ebay is flooded with fakes. Some are better some are worse. Anything you buy there is most likely not genuine and very often has different (worse) parameters than original. \$\endgroup\$
    – Chupacabras
    Commented Aug 22, 2019 at 13:43
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    \$\begingroup\$ @nonoitall - I've edited your question to make it less of a shopping question so it can hopefully be reopened. Feel free to revert or edit it yourself if I've changed it too much from your intention. \$\endgroup\$
    – Justin
    Commented Aug 22, 2019 at 13:48
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    \$\begingroup\$ Keep in mind that you cannot use an NFET to control power to systems that need to share signals with your Arduino (ie, situations where a common ground is required); for that you need to switch the positive rail - ie you would need a PFET to or a complicated circuit to drive an NFET on the high side. Also keep in mind that you must not apply signals to most devices when they are powered down, as signal voltages are typically prohibited from being more than a tiny bit outside the range of supply voltages. Also remember that a pi should never have power removed until after soft shutdown. \$\endgroup\$
    – Chris Stratton
    Commented Aug 22, 2019 at 13:50
  • \$\begingroup\$ Probably you should start by replacing the pi with something that has low power sleep modes; basically something with an SoC originally intended to be a tablet, instead of originally designed to be a set top box with mains power. \$\endgroup\$
    – Chris Stratton
    Commented Aug 22, 2019 at 13:52
  • \$\begingroup\$ "with a max Vgs of 4V." That's not Vgs, that's Vgs(th). And no, it definitely does not guarantee what you want; Vgs(th) defines when the mosfet is no longer "fully off". It says nothing about when the mosfet is "fully on". \$\endgroup\$
    – marcelm
    Commented Aug 22, 2019 at 20:00

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The IRFB3006PBF should work fine although it's QUITE an overkill, pretty sure the datasheet you linked is for a different transistor though (that one should work fine too and I think that's the one you meant to ask about). The graphics in the datasheet should help you determine how much current can the the unloaded transistor pass at a given GS voltage, in the case of FQP13N10L that's well over 10A. Hope that helps.

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