The LED's votage is the most important. Forget the current. 2 Amps is MORE than enough to power all the LEDS you can fill your CP with! ONE LED draws typically 20mA. It is NOT the power supply that pushes the current through the LED's. The LED's are DRAWING current from the PSU. The current a LED draws depends on the voltage it's being given. If you give the LED too much voltage it DRAWS more current from the PSU and vice versa. But the LED's operates between limited voltages. Most LEDs have a voltage drop between 2-3 volts. White ones are usually higher, around 3.5 volts. But with resistors in serial with the LED('s), you can operate them with higher voltages. Even the cheap white LED strips you buy from ebay that operates on 12 volts usually uses groups of 3 LED's in serial (3 x 3,5 = 10,5V) + an additional resistor. And these three LED's draws 20mA in TOTAL (because they are connected in serial).
The OP just indicated intent to use 128 RGBs (60ma each when all three elements are lit) which comes out to 7.68 amps. The outputs on his controllers are constant current (not by resistors) set to 20ma per element. Trying to run all of those on a 2 amp supply will cause something to smoke in short order. Slippyblade was entirely correct in his statement that the total of the load (current required) must be less (significantly less in some cases) than the rating on the supply.
The methods used in LED strips are not applicable in this situation, where individual control of each LED is desired. This is why even smaller visual displays, made from smart LED strips, require a crazy amount of current, usually delivered through heavy gauge wire connected to multiple power supplies.
Properly regulated voltage and sufficient current availability are both very important factors when selecting a power supply.
Any particular brand recommended?
No. The power supplies on our store (more coming in a few days) will have either 15 or 16amp stamped on the 5vDC output. I have not tested them at full load, so the rating is likely optimistic. Given that you only need about half of the stated current availability, they are probably a safe bet. They also have a control for fine tuning the 5vDC voltage output, so that's a good feature. My best advice is to pick one which suits your needs and one which has a control to trim the output of the supply to the voltage you are looking for. Your controllers may have other requirements I am not privy to, so you should direct those questions to the manufacturer. You probably have a little more wiggle room with the voltage, as those controllers use constant current outputs. But it's better to be able to get the voltage as close as possible to what is needed, to avoid creating more heat in the other components than necessary.
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Topic: 5v LED Power Option (Read 6513 times)
