I would like to provide external battery power to the CUI32.
My PCB underside says "3.5-10V" at the battery connector (by the way, on the PCB photo on sparkfun it seems the PCB says "3.5 to 5.5V !??) but from the schematic it is not clear to me if I can directly connect a 9V battery (for example). To me it looks like this would put 9V on the 3.3V DC/DC input (which would be OK) but as this is normally 5V (when USB powered) it seems I would get 9V on the USB pins and also on pin34 of the PIC (which is conncted to the 5V). Having the 9V on the PIC looks very unhealthy to me.
To cut it all short: Can I directly connect a 9V battery (and if, why) or do I need a 5V regulator (or similar) ?
Many thanks !