P-Channel Mosfet

What is the difference between a PNP transistor and a logic level FET?

I've been looking online but cant find any information delineating between the two.

A P-channel MOSFET will generally have a lower ON resistance than a PNP transistor. This makes them good for switching high currents.

A MOSFET also requires very little input current and has a high input impedance so you don't need the 'base resistor' used with a transistor.

A logic-level MOSFET will saturate at a low gate voltage, like 3 or 5 volts, so you can hook it directly to a logic pin. Most MOSFETS seem to have their ON resistance specified at a gate voltage of 10V.

Note that if the voltage the MOSFET is switching is much higher than the Arduino output you will likely need a small NPN transistor (with it's base resistor) to switch the MOSFET gate.

What is the difference between a PNP transistor and a logic level FET?

Well one is a transistor made from three different layers of doped silicon and the other is a field effect transistor made essentially from one bar of silicon with a diffused gate. Do you mean a p-channel FET? or an n-channel FET. I will assume the former.

A MOSFET also requires very little input current and has a high input impedance so you don't need the 'base resistor' used with a transistor.

When use with the arduino it is best to put a 100R resistor in series with gate to limit the charge current to below the 40mA maximum allowable current.

Otherwise as above. :)