IRF520 Mosfet module

I am using the IRF520 mosfet module to dim my high power LED by using pwm.

An example of the simple circuit can be found here;

When i connect the gnd from the mosfet to the gnd on my uno, it works, but when i connect the gnd to the gnd of a 5v voltage regulator, the mosfet module stopped working? I tried connecting to other external gnd pins but nothing works, so far only the gnd pins on the arduino works. Can anyone help?

If the arduino is still on the picture, then ALL GND pins must be connected to each other.

Also, what is the IRF520 module you speak of? Does it create the correct 10V GATE voltage that the IRF520 needs to fully conduct?

The IRF520 MOSFET won't work with Arduino.

Use a logic level MOSFET instead, like this one.

All grounds must be connected.

That board is yet another example of a dishonest vendor claiming that a non-logic-level MOSFET (IRF520) is suitable for use with 5v on the gate. It works kinda at low currents (2Aish, see figure 1 in datasheet for IRF520), but will not work at higher current, and will overheat if you try.

DrAzzy:
That board is yet another example of a dishonest vendor claiming that a non-logic-level MOSFET (IRF520) is suitable for use with 5v on the gate.

It's a pity that, because for the beginner and or for prototyping, a suitable mosfet on a board could save a lot of buggering around with resistors and decent connections for the power side (rather than breadboard). (Although it doesn't have a flyback diode bulit-in according to the schematic.)

Try IRF3708 or IRL540N

Welease_Woggah:
It's a pity that, because for the beginner and or for prototyping, a suitable mosfet on a board could save a lot of buggering around with resistors and decent connections for the power side (rather than breadboard). (Although it doesn't have a flyback diode bulit-in according to the schematic.)

Modern high power MOSFETs all have diodes built-in, its inherent in the structure of the device. Note this
doesn't apply to IGBTs or darlingtons (although some add them anyway).

MarkT:
Modern high power MOSFETs all have diodes built-in,

That's two things I learned about mosfets this week.

The build-in diode of a mosfet can't replace a flyback diode, because it's in the wrong place.

A flyback diode goes across the load, not across the mosfet.

No flyback when switching high power LEDs, so no diode needed.
Leo..

Welease_Woggah:
It's a pity that, because for the beginner and or for prototyping, a suitable mosfet on a board could save a lot of buggering around with resistors and decent connections for the power side (rather than breadboard). (Although it doesn't have a flyback diode bulit-in according to the schematic.)

You mean, something like this?


(Obviously - or maybe not obviously - that's a link to my Tindie store)

Thanks for all the inputs. I've decided to use the mosfet anyway as it is easier with a module than to construct one with another mosfet. (Or perhaps i should just remove the IRF520 mosfet and solder another on the module?)
I'm thinking of adding a mosfet to a LED driver to try to dim the LEDs. I've had a lot of success using LED drivers whereas the LEDs with power resistors tend to stop working after awhile. Has anyone tried that?