TLDR: Can I power an Arduino Uno and CNC Shield from a MW LRS-350-12 if I use a buck convertor down to 9V 2A (18 W)?
I am in the process of building an ERC TimSav Foamboard cutter. I want to be able to use a single power supply for both without going through the CNC shield as he suggests (others have had issues doing this, but they were also using different brand boards).
I am still in assembly, but I just found out after checking that the 12v 4A DC power supply is probably too much power for the Arduino.
So since I have already have the power supply I thought I could power the CNC Shield directly off the power supply and used a buck convertor to bring it down to 9v 2A and then I would only need the one power supply.
I was thinking of this one:
I thought I should come to experts since you know way more than me by a long shot
That would work,but if you are going to use a converter, why not use a 12V to 5V converter? That way you connect to the Uno 5V pin and bypass the weak onboard 5V regulator.
I would go with GroundFungus proposal.
It is also a method I have used here with success.
Prefer the caged droppers myself though as they seem to last.
2A variety should also give you some wiggle room for extras such as relays / mosfets etc.
groundFungus:
That would work,but if you are going to use a converter, why not use a 12V to 5V converter? That way you connect to the Uno 5V pin and bypass the weak onboard 5V regulator.
I was just going with what I had read that 9V 2A was the best power to use. I can try this first though and if I have issues, change it out as needed.
I was just going with what I had read that 9V 2A was the best power to use.
That is not too bad, but not the best way. If you use 9V into the power jack or Vin, you will be using the onboard 5V regulator to power everything on the 5V line. The on board 5V regulator is not heat sinked so will handle a limited amount of current (about 200mA) before it overheats and shuts down. Using a DC DC converter and connecting it to the 5V pin bypasses the weak 5V regulator and provides the rated current of the DC DC converter to the 5V line.
groundFungus:
That is not too bad, but not the best way. If you use 9V into the power jack or Vin, you will be using the onboard 5V regulator to power everything on the 5V line. The on board 5V regulator is not heat sinked so will handle a limited amount of current (about 200mA) before it overheats and shuts down. Using a DC DC converter and connecting it to the 5V pin bypasses the weak 5V regulator and provides the rated current of the DC DC converter to the 5V line.
So really there is no use using 9V as it gets reduced to 5V anyways. I can pick up two of these for the low cost of $10 and change and just wire it in.