Connect arduino to RGB strip? (IRFZ24N)

Forum 2005-2010 (read only) Hardware Interfacing
1

Hi guys,

I want to control RGB strip (12V and ~2A) with my arduino. Im beginner in electronic, but I read that IRFZ24N should work well for my project.

But Im tinkering many hours around and cannot succesfully connect things together.

  1. Arduino works. Im using simple LED blink example - and just want to make my strip blinking like builtin LED in arduino.

  2. LED strip works.

  3. IRFZ24N works - when I connect gate to 0 or +12V of my power supply, LEDs goes on and off correctly (I know +12V is too much for this transistor, but it is still alive).

When I connect everything together and connect transistor gate to arduino pin, strip is always switched on and just strip light intensity is little changing when arduino's internal LED is turned on.

So I see that something happen, but how should I control strip in full range (full off - full on)? Am I missing something in transistor specs? Maybe I don't understand how to work with two power supply circuits - is there something to read about this for beginners?

Please help, Im out of ideas and Im angry that I spent too much time with such easy thing :'(. And sorry for my English.

Marek

2

Here is a pretty good list of common causes of MOSFET failures:

The MOSFET you used was not logic level MOSFET so it can't drive by the arduino pin, you need a BJT transistor to pull the gate to 12V.
your MOSFET need a resistor of 10K connect gate to groung.

3

The IRFZ24 requires about 10V to fully turn it on, the gate threshold is only when it starts to turn on, that's why you see it only dimly. You need either a logic level FET, or a transistor to drive the gate to a high voltage.

I know +12V is too much for this transistor, but it is still alive).

No that is fine for this FET.