Pin voltage problem

Other Hardware General Electronics
1

I need to activate an IRF530N from Arduino. I hooked the output pin through a 220 Ohm resistor and connected gate to source with a 10k one. For testing I connected an LED to the mosfet. When the output is set to high the LED doesn't light up, though if I connect the gate to the 5v rail everything works fine.
I tried connecting the output pin directly to the LED and the light is much dimmer that when connected to 5v.
I suppose the output voltage of the pin is much lower than 5v.
I don't explain myself why the voltage is so low... the nano board I'm using is brand new and the only other thing I have connected is an I2C LCD, though nothing changes if I try without it.
how can I work around this and make the mosfet work?

Thank you

2

davidoskky:
For testing I connected an LED to the mosfet.

How?

3

Cathode to drain, anode to 5v through 220 ohm resistor

4

Did you set the pin to OUTPUT with pinMode();

The IRF530N is not a logic level mosfet, and won't get in full saturation with 5volt at the gate.
It might just work with a light load.
Leo..

5

That's not a logic level MOSFET. It needs about 10V on the gate to switch on fully. You might have more luck with an IRL530 which is the logic level equivalent.

Steve

6

But with light load, like a single LED, it should work just fine.

I bed he did not set the pin to output :slight_smile:

7

Wawa:
Did you set the pin to OUTPUT with pinMode();

Thanks that was it... I made someone else write the code and I just assumed it was right!
Thanks to everyone for helping me out; now that it works I'll gladly go out and take an actual logic level mosfet.