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Fast square wave with arduino and mosfet

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ManlishPotato:
Hey y'all
I'd like to make a tank circuit with a coil and capacitor in parallel. To power it i need a really frequent square wave. 1 mhz would be nice but maybe about a 500-600 mhz minimum. I was thinking of using a arduino directly interfacing the ports to produce the wave, using it to control a mosfet to power the circuit.
Yet the signal pretty much stays the same no matter how much i increase the voltage. I cant't check exactly want the value was right now , but i thing it hade about 1-2v voltage drop across the mosfet which seems like a lot, and like i said i cant get the voltage top much higher than 4.5-4.9v. It had peaks of about 5.2 i think.

Is this the wrong approach? How could you accomplish this for cheap?
Thanks in advance
//Benji
https://imgur.com/a/JjfIlp2

MarkF:
The Arduino pin voltage is not high enough to turn on the MOSFET if you have the load on the low side as you have it.
You want your tank circuit on the high side.  Even so, you will need a logic-level MOSFET in order to fully turn it on.

ManlishPotato:
Isn't FQP30N06L logic level? Also, with the voltages i measured i had no load connected, like in schematic, i had only the oscilloscope connected.

ManlishPotato:
BTW, why do you use i resistor in series to the gate of the mosfet, isn't mosfets voltage driven unlike bjt's?

MarkF:
- I had not looked up your MOSFET.  A quick look appears like it is.

- In your circuit R1 is the load.  Which when the MOSFET is turned on the voltage across R1 rises and will turn off the MOSFET unless you raise the gate voltage to compensate.  (The load is on the low side.)



- The series limits the gate current.  A MOSFET gate has a capacitance which you charge when you apply a voltage.  Also, you can have oscillations without the resistor.

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