I just bought cheap rgb light strip and I do want to cotrol it from arduino.
It have +, r, g, b pins on it. I connected positive to 12v and other pins to ground and It producted white light as it should.
Arduino nano can make pwm and range is 0-255, I couldn't connect it direcly to arduino because of current and voltage limits. I used irf9540n mosfet to control one color, there were three of those mosfets to control every color channel, but even when mosfets gate is connected to ground the led strip isn't fully light up and it can't product white light.
Hi,
I'm not an expert in MOSFET, but I think that what you are using is not for logic level.
Search here in the forum and you will find dozens of topics about the use of "logical" MOSFETs.
It is an inverting circuit... When the gate is high the drain goes low but since it's "ground side switching" current flows through the load and a high on the gate turns the lights on.
A P-MOSFET has to be connected on the high-side but a single MOSFET doesn't work if you are controlling/switching 12V because to turn it off you need 12V on the gate (in order to get zero volts between the source and gate).
You can leave-out the diode since you have a non-inductive load.
