Sorry if this has been asked before, I tried to find an answer, but I couldn't find one that meets my criteria.
I would like to use the 5v pin and ground on my Arduino Uno to power a 3.5m string of 50 RGB LEDs (Amazon.com). Is this possible, or do I need an external power supply?
I need a lot more education on AC/DC/ohms/amps, but for an ignorant person like me, the pin says 5v and the LEDs say they need a 5v power supply, right?! I want to make my project portable, so I do not want to plug it into a wall.
I will be powering the Arduino using a usb lip-stick charger like this one, Amazon.com.
If you don't want to plug it into a wall, you will need a good battery source. Using several 18650 cells, in holders, with a converter will last for a little while.
But first off, no, you cannot power that many LEDs through an Arduino. Just because it says 5V on both, you are leaving out current (Amps).
There's a reason you can't start your car with 8 AA batteries taped together, even though that gives you 12-14V.
If this is going to be portable, you will have a battery pack, one power line going to the Arduino, another power line going to the LEDs. You will probably control the LEDs through a MOSFET.
Hey guys, i think my question is related, thus i prefer to ask here instead of making new post. My project wants to drive 60 WS2812b led strip with arduino. I know that it is impossible to power the strip by the Vin of the arduino because of the amount of the current the leds will need. So, searching on web, i found this project:
I think this would be great in my case. However, (NOTE i am not good in elettronic) i think that when i power up the system, leds will turn on without any control by the arduino. I would plug the power supply to the system, then the uController will decide whether turning on/off the led strip or not.
Could a transistor be my solution? If yes, which one? Any advice on how to insert it in that schema?
Thanks Guys!
WS2812B doesn't just turn on with power. It needs data. But it may remember the previous data if it was unplugged abruptly.
Anyway, the diagram is okay if that '5V power supply' has the amperage required. So no transistor is called for anywhere.
Yes, you could put a Logic Level, Low Rds P-channel MOSFET between +5 and the Strip's 5V pin to keep it powered down until you are ready to send it data.
Will be hard to do much better than this one, performance/cost wise.
