Because these LED strips are very simple, we can easily use them with any microcontroller. We suggesting 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 STP16NF06
- they are very popular and inexpensive. 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 STP16NF06'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.
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.
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!
Last updated on 2014-04-19 at 09.20.22 PM
Published on 2012-11-26 at 09.21.02 PM
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.