Just a quick question, is it ok to power the pro mini using a battery on the raw pin, and having the 6 pin ftdi plugged in at the same time? I know the bigger arduinos can power auto select but am worried about blowing up the pro mini. I would like to program and debug while having the battery plugged in.
thanks in advance
First, connect the battery to the VCC pin (3 AAs work well, but keep it under 5.5V no matter what) so you're not wasting amperage on the regulator.
If more than 6.5V, go thru Vin.
Second, there is no autoswitching - if you connect both using VCC, the USB will try & source current into the battery. Or the the regulator will try to drive the USB source. Not good either way.
Does the FTDI have a way to disconnect the VCC output pin?
3v3 or 5v Pro Mini?
I have the 3v3 version. I have pulled the 5v vcc wire from the FTDI cable and plugged it into the RAW I/P line.
This is because the 3v3 FTDI 232 cable still supplies 5v to the VCC line.