I am working on an Arduino project and am confused by how to power the Arduino without USB. Here is the Arduino that I have:
I believe this is the schematic of the board:
I have been able to program “blink” with the USB cable. Blink works.
But, if I disconnect the USB cable and try to power the device from +5VDC, the light on the board stays on; no blinking.
My external +5VDC is provided by a linear regular from a 12V vehicular battery. So, the external power is accurate and stable without ripple, etc.
Looking at the schematic, it appears that 5V from the USB goes to exactly the same place as the 5V pin.
Any ideas what I could be missing? Here is a video we took this morning to illustrate the behavior:
Note that, in the video, the USB cord continues to be plugged in. But, the external power is not applied. I.e., the regulator is not providing any power. The 5V regulator and GND are the only pins that are hooked up to anything when the Arduino is plugged into the socket.