27-10-2015, 02:31
"The board has a simple two resistor voltage divider wired to the Vin voltage, if there is a voltage of sufficient voltage, a op-amp comparator circuit switches off a MOSFET switch that then isolates the USB voltage from the board's Vcc bus. So if there is both USB voltage and Vin voltage available, then the Vin voltage takes priority and is used to power the board. "
One correction: The above applies only to UNO, the Nano does the same function in a more simple way, it uses only a diode!
Regarding this concern: Sometimes I mount the nano with sockets, others I solder it directly on the board, but when I choose to solder it on the board, I use the full pin length, to keep it raised relatively to the RX board, this allows a better air flow (the nano voltage regulator is assembled in the underside of the Nano board)
One correction: The above applies only to UNO, the Nano does the same function in a more simple way, it uses only a diode!
(26-10-2015, 06:19)Palmyweather Wrote: Just wondering, was the Arduino Nano soldered directly onto the circuit board, or was an IC holder used first with the Arduino Nano mounted afterwards?
If soldered directly onto the circuit board, could excess heat maybe have damaged some of the sensitive components on the Arduino Nano resulting in this kind of issue?
Regarding this concern: Sometimes I mount the nano with sockets, others I solder it directly on the board, but when I choose to solder it on the board, I use the full pin length, to keep it raised relatively to the RX board, this allows a better air flow (the nano voltage regulator is assembled in the underside of the Nano board)