I am planning on wiring my circuit exactly from a project I found on the Project Hub. (Schematic Image Attached)
I will be using a DC 5v 2A power supply to power the LED Matrix and Arduino UNO. From what I have been reading online using the UNO 5v pin is more vulnerable than the USB / 2.1mm plug.
Is this okay to run my power supply directly into the Arduino 5v pin? Or this there a better practice I should be using? Does the 5v pin have a maximum current input?
The Arduino will only draw the current it needs.
If you are not connected to a PC/USB, there is no problem powering via the 5V header pin. Just don't do both at once, the PCs don't like that and may shut down the port (or worse), my Lenovo just required a PC reset to recover; other types, who knows?
Power the LED matrix and the UNO in parallel from your supply as you have shown.
But do be aware that you can damage your board if you have it powered through the 5v pin and plugged into USB. Don't do that.
What I recommend doing is chopping up a USB cable and connecting that to your 5v supply, as that will then physically prevent you from connecting both USB and 5v pin to power at the same time. Lots of people power boards off USB phone chargers, so you don't even have to rewire a cable.
DrAzzy:
What I recommend doing is chopping up a USB cable and connecting that to your 5v supply, as that will then physically prevent you from connecting both USB and 5v pin to power at the same time. Lots of people power boards off USB phone chargers, so you don't even have to rewire a cable.
Cool idea. I dont think that will work since my LED matrix will use 600 mA.