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I have an Analog 12V RGB LED strip (which only requires 1-2 amps at most) that I want to control using an Arduino Uno. I looked into how I could go about doing this and saw that i could use several Logic Level MOSFETs to control the RGB pins on the LED strip.

I intend for the Arduino to send PWM signals to the gate (with a 10k pulldown) to control the brightness of the LEDs.

I can easily get hold of some STP55NF06L N-Channel MOSFETs which I initially thought should be able to do the job since the Gate Threshold Voltage is 1.7 volts. However I read too much off of the internet about what MOSFETs can be used with Arduinos and now I am unsure if they will work. One website told me one thing while someone else told me another. There was a lack of a clear cut definition.

Will these MOSFETs work with the 4-5V signal from an Arduino? If not, can you suggest any alternatives?

Also, if anyone can explain what should I be looking at in the datasheet to help me figure out if they are logic level, I'd be extremely thankful.

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Forget Vt. What you should look at is Rds(on) at 5V drive which is 0.02 ohm maximum (will increase with heating, but not more than 50%). At 2A the heating will be no more than 120mW so you won't be needing a heat sink for static switching (you can verify my latter claim from the thermal characteristics). The 0.02 ohm is a 100% tested guarantee by the manufacturer, not a "typical" characteristic, which may or may not be accurate for any given device.

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If your PWM frequency is high, there may be significant heating from the slow switching due to not having a high current gate driver but at a few hundred Hz it will almost surely be fine.

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Figure 3 (Output characteristics) on your datasheet shows us that this device will easily allow 2A of current with 4V driving the gate, with room to spare.

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