Programmable LED strips are fantastic when it comes to adding color patterns to almost anything. But one thing to keep in mind is the power that will be required to run them. Yes, LEDs use much less power than incandescent lights, as most of us know from buying them for our home lighting, but they still require some power, and it may be more than you think.
The Pixent programmable LEDs in RGB format will use up to 12 milliamps of 5 Volt power for each die, or 36 milliamps of power at full output. A milliamp is one-thousandth of an amp, so that means that a normal 1A USB phone charger could power only about 27 LEDs. You can run the LEDs at about 2/3 output power and still get a very acceptable light output (see my previous post on gamma correction), and this will save you power. But to be safe, you should always size your power supply such that it is capable of powering your entire string of LEDs at full output with some small amount of margin to spare.
For a 5 meter strip using 60 LEDs per meter, this will be about 300 LEDs. 300 times 0.036 is 10.8 amps. Add in some margin, and you’ll need an 11A power brick for that strip. What happens when you do not supply enough power? The LEDs at the end of the strip begin to suffer from voltage drop, and they will either cease to work completely or will render the wrong color because the internal controller cannot provide a constant current to them.
Once you figure out your power needs, contact Summitech for information about our line of consumer and commercial power supplies; available in myriad different sizes and output voltages.
