Because these LED strips are very simple, we can easily use them with any microcontroller. We suggest using PWM dimming techniques to control the strip. Since each 'LED' pin may end up requiring an Amp or more to sink to ground, power transistors are required! Don't try to connect the pins directly to your everyday microcontroller, they will burn out and/or not work.

You can use any power NPN or N-Channel MOSFET, make sure the transistor is rated to be able to pass as much current as you need. For example, since we draw about 0.2Amps per channel per meter, if you have a 5 meter strip you will need to pass up to 1 Ampere per transistor. Get the beefy "TO-220" packages, not the dinky little guys. Make sure they look like this:

For basic, low-cost usage we suggest using N-channel MOSFETs such as the IRLB8721 - they are very popular and inexpensive and work with 3.3V or 5V logic. If you can't get those, TIP120 are also good but there is more voltage loss in a transistor than in a MOSFET which is why we suggest those first (less heat loss, more light!)

This diagram shows connecting up with N-Channel MOSFETs where the Gate is pin 1, the Drain is pin 2 and the Source is pin 3

The IRLB8721's can handle up to 16 Amps of continuous current - so that's at least 750 LEDs, and if you don't have them all on bright white, 1500 LEDs. You may need to heat sink depending on the continuous/overall power draw/dissipation

For longer strips requiring more than 1 Amp, wire the power directly to the strip, then run power and ground wires back to the Arduino.
This diagram shows connecting up with power NPN transistors such as TIP120, where Base is pin 1, Collector is pin 2 and Emitter is pin 3. Its very similar except this time we have 100-220 ohm resistors between the PWM output pin and the base.
For longer strips requiring more than 1A, wire power directly to the strip, then run power and ground wires back to the Arduino.
Connect a 9-12V power supply to the Arduino so that Vin supplies the high voltage to the LED strip. If you want, you can also just use a separate wire that connects to a power supply that provides about +12V. Make sure to connect the ground of that supply to the ground of the Arduino/MOSFETs!

TIP120's can handle up to 5 Amps of continuous current - so that's at least 250 LEDs, and if you don't have them all on bright white, 500 LEDs.

This guide was first published on Nov 26, 2012. It was last updated on Mar 14, 2024.

This page (Usage) was last updated on Nov 26, 2012.

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