LowPowerLab Forum

Hardware support => Moteino => Topic started by: john k2ox on October 17, 2013, 05:16:12 PM

Title: +12v
Post by: john k2ox on October 17, 2013, 05:16:12 PM
I'd like to know if anyone has powered a Moteino with 12 volts and used LP Labs FTDI interface with it?  I was worried that the 12v would flow into the FTDI chip and fry it.

I opened the 5v jumper and put a diode across it.

Just wondering if I could have gotten away without it.
Title: Re: +12v
Post by: Felix on October 17, 2013, 09:29:12 PM
Hm, there's no reverse voltage protection from the FTDI adapter because the point of it is to power the Moteino when programming it only, or while attached to the computer for debugging/testing. It could also be used when deployed, but then power should be provided from the USB input of the FTDI adapter.

So .. I would not advise powering the Moteino from VIN with 12V while the FTDI is attached.
Also, 12V is a bit of a stretch, while still within the 13.2V max input spec of the little regulator, it's not a switching regulator so the more voltage the more heat it will dissipate. I powered Moteinos from 9V many times without a problem. And I tried to always stay at or below 9V. Not saying that 12V doesn't work but if there's a choice, a lower voltage should be picked.