I apologize if this is a stupid question, but my understanding of power and Arduinos are both very limited.
Here's the scenario that I'm working with:
I have a 12v, 10w power source for my Arduino and for a 5v, 500mA gas flow valve.
I would like to know how this could be wired into an Arduino MKR1000 so that I could periodically turn on the valve using the required 5v, 500mA and still power the Arduino off of the 12v, 10w power source. (The valve is off by default and would need to be powered for 1-10 minutes periodically.)
Is this doable, or am I just having a pipe dream?
Thanks for any help you can provide,
Riley
I apologize if this is a stupid question, but my understanding of power and Arduinos are both very limited.
That's correct. The Arduino's I/O pins are 5V low-current signals, not power so you can't directly power much more than a couple of LEDs. Also, the Arduino's on-board 5V regulator can power some more electronics, but it can't power a motor or solenoid.
You'll need a [u]driver circuit[/u] and a 5V power source for the solenoid valve.
This can be done, but it would be better to get a 5V power supply (for both the Arduino and valve), or get a 12V valve...
I have a 12v, 10w power source for my Arduino
10W @ 12V is 830mA, so that's enough for the Arduino & valve, but... You'll need a 5V regulator. 500mA is getting to the point where a simple linear voltage regulator is going to get hot and possibly overheat. Even a "1A" rated voltage regulator may overheat.* A switching regulator is nearly 100% efficient, and I'd recommend a switching regulator.**
- The head is due to the power wasted in the regulator, which is the voltage dropped across the regulator (7V in your case) x the current. The more voltage you drop, the hotter it gets.
**The efficiency of the regulator means that you can feed-in 12V at a little more than 200mA, and you can get-out 5V @ 500mA for your valve.
Thanks for the response! I will make sure to use what you told me as I proceed with the project.