I know the specs say the Arduino Mega 2560 R3 has a recommended Voltage of 7-12vdc. But I have a 5 volt / 2.5a wall worth PS that was used to power a USB hub. Will that work? Or do I need to supply a min of 7 volts?
Seems to me it should work with 5 v as when it's connected to a computer via USB it's only supplying 5v.
Thanks
If you connect it to the correct 5V pin(s) it will work fine. If you connect it to the other inputs that need 7V then it won't.
Steve
I've been researching this a bit more and the documentation is a bit confusing.
I'm thinking the best way to power would be through the USB port. Just take a USB cable and cut the end off.
Or is the 5V where I would connect. But I see it would be advisable to add a diode.
If the 2560 is powered from with a through the barrel connector does the 5V become a reference voltage?
Is the Vin for 7-12 v input/same as the barrel connector?
Thanks
The only difference between the USB socket and the 5volt pin is a 500mA polyfuse inline with the USB socket.
Adding a diode would lower the external 5volt supply with a diode drop (0.4-0.7volt).
If you're careful not to reverse polarity, then don't use a diode.
The only difference between V-in and the DC socket is a diode inline with the DC socket.
Not a problem here to drop 0.7volt from a still unregulated voltage.
6volt on V-in (6.7volt on the DC socket) is the absolute minimum for the regulator to make a stable 5volt.
Leo..