Separately power Arduino and LEDs with one power supply

Other Hardware Motors, Mechanics, Power and CNC
1

Hi,

I am currently working on a project where I need to power quite a few RGB LEDs. Because the LEDs use about 60mA when on full brightness, I need to power them separately.

Now here's the thing: I'd rather not have to use 2 power supplies to power the Arduino Micro and LEDs, so if possible I'd like to use the same power supply (5V/10A). Is this possible? To help illustrate my point I added a simple representation of my idea.

Thanks in advance.

– Wouter

psu-arduino-leds.png

2

what voltage power supply are proposing to use ?

If you get, for example, a 12 V 10 A power supply ( supplied with A/C mains electricity ), then you power the LED's with 12 V and you can convert the 12V to 5V ( or 3.3 V ) to supply the arduino. You can buy compact cheap DC to DC converters to do this.

You also need to consider how you are actually going to control the leds with the arduino.

3

The LEDs also take 5V, so I was planning to use a 5V/10A PSU. Even though this is more power than I actually need, it can't hurt to have a few extra amps. But what I am mainly concerned about is if this setup is possible without frying anything.

I already have the code necessary to control the LEDs as Adafruit has a library to do this pretty easily.

– Wouter

1 Like
4

Can anyone confirm if it possible to hook up a power supply like this?

– Wouter

(also a shameless bump)

5

I have done something similar and it worked.
Note: if conditions are not ideal, you may experience noise on the 5 volt line which may cause intermittent problems. (keep an eye out for this)
In my opinion however, I would recommend a separate supply for the Arduino, they are cheap. (add a common ground to the LED supply of course)

6

Hi LarryD,

Thanks for the answer. I'll give it a try and if I experience any problems I will have to go with 2 psu's.

– Wouter