Driving mosfet with Arduino UNO

Other Hardware General Electronics
1

Please help!! I need to control a irfp250 or irfp460 mosfet with arduino PWM signal but the arduino does not have enough power to control it.What I need to do in this situation?

2

Mod edit:
Text below is AI generated, while it might be correct and helpful keep in mind that AI tends to hallucinate when it doesn't know something.

Hey there! It's awesome you're diving into controlling MOSFETs with your Arduino. That's a really cool project! You're right, sometimes an Arduino's output isn't strong enough to directly switch those bigger MOSFETs like the IRFP250 or IRFP460. Here's a breakdown of why and how to fix it:

Why the Arduino Struggles:

  • Gate Charge:
    • MOSFETs need a certain amount of electrical charge (like filling a tiny bucket) on their "gate" pin to turn on fully. Those IRFP series MOSFETs have relatively large gate charges, meaning they need a lot of that "charge" to switch on, and off, quickly.
    • Arduino pins can only supply a small amount of current, so it takes them a while to "fill that bucket," which can lead to the MOSFET not switching efficiently.
  • Switching Speed:
    • If the MOSFET switches slowly, it wastes power as heat. This is especially important when using PWM (Pulse Width Modulation), where you're switching the MOSFET on and off rapidly.

The Solution: A MOSFET Driver!

The best way to solve this is to use a dedicated MOSFET driver. Think of it as a little helper that takes the Arduino's weak signal and boosts it to a strong signal that can quickly switch the MOSFET.

Here's why a MOSFET driver is your friend:

  • Increased Current:
    • MOSFET drivers can supply much more current than an Arduino pin, allowing the MOSFET to switch on and off rapidly.
  • Faster Switching:
    • This leads to less heat and more efficient operation.
  • Signal Level Shifting:
    • Some MOSFET drivers can also shift the Arduino's 5V signal to a higher voltage (like 12V), which some MOSFETs prefer.

How to Use a MOSFET Driver:

  1. Choose a Driver:
  • Look for MOSFET driver ICs (Integrated Circuits) like the TC4427 or similar. These are designed specifically for this purpose.
  • Also pre made modules can be found online, that simplify the process.
  1. Connect It:
  • Connect the Arduino's PWM output to the driver's input.
  • Connect the driver's output to the MOSFET's gate.
  • Make sure to connect the driver's power supply and ground correctly.
  1. Enjoy Controlled Power:
  • Now, your Arduino can control that powerful MOSFET with ease!

Important Safety Tips:

  • Always double-check your wiring before applying power.
  • MOSFETs can get hot, so use a heat sink if necessary.
  • Be careful when working with high voltages and currents.

I hope this helps you get your project working! Have fun!

3

What are you trying to control with the MOSFET?

I didn't check the datasheets for the MOSFETs you mentioned but a "logic level" MOSFET can be switched fully-on with 5V.

Here is a MOSFET circuit for controlling a motor. It will work with PWM if you want to control the speed of the motor. If you have a non-inductive load you can leave-out the diode.

4

Hi, @s4rd3l
Welcome to the forum,

Do you mean output voltage to operate the gate?

Can you post a schematic and code of your project at the moment?

Thanks.. Tom.... :smiley: :+1: :coffee: :australia:

5

The mosfets you quoted are not logic level.
You can use them, but only for light loads.
Change to logic level fets if you need to switch more than a couple of Amps.
Leo..

6

I want to control a slayer exciter with it

7

Yes, when i measure the voltage at mosfet's pins it only has 1.5V not 5v

8

Sure! Whatever that is... :upside_down_face:

9

Then high voltage non logic level mosfets with mosfet drivers might be the only option.
Leo..

10

I was hoping for an explanation and got a like :upside_down_face:

11

I gave you one too because I have no idea what the OP's talking about either and was glad I wasn't the only one!

12

I don t have a schematic yet.It s just a mosfet that drives a slayer exciter, but i need to control it with PWM signal to operate and I don t have enough current to open and close the gate

13

Sure, lets give likes :wink:

Slayer exciter sounds like something you find on level 7 in a very gory game.

14

Turns out it's a Tesla coil more or less. Not quite as exciting (usually...).

15

Except in a computer game you don't die for real.

Now back to @s4rd3l and his slayer exciter, our reporter is at the scene...

16

A mosfet gate needs very little current.
I think you mean voltage.
Leo..

17

The arduino sends 5v to the mosfet but it only gets 1.5v so the signal doesn t have enough power to control the gate

18

Post a circuit diagram.
Did you set the pin to OUTPUT with pinMode.
Did you measure that 1.5volt with a scope. A DMM will average PWM.
Leo..

19

I don t have a scope but yeah i set the pin with pinMode on pin 9

20

Both have Rds(on) rated at Vgs = 10 V which concludes they are not suitable to work with your Arduino (5 V). In other words, lets skip this track:

If we work from a different angle; Since the FET's you have chosen(?) are rated at quite different voltage and current which makes it hard to read out the requirements - what is needed to drive this tesla coil?