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I've been thinking about this very interesting post on heat generation from "linear" regulators.
I've always assumed the heat generation was some sort of exponential, and the "linear" referred to something else (as it may do).
The real issue in practical operation is of course really heat dissipation as well: can the heat generated be sufficiently rapidly dissipated to stop the components exceeding their maximum operating temperature (if necessary with the use of a heat sink or fan).
Is there a useful rule of thumb to take account of this without monitoring the temperature of a chip in actual operation?
Not really, the better approach is to use the design information provided by the manufacturer of the regulating device. They know the thermal transfer characteristics of their device, and publish design criteria for heat dissipation.
The indicated area has the possibility of the solder side of the header pins shorting out on the grounded shell of the USB socket.
Put a couple of layers of insulating tap over the socket shell to prevent any short circuit if you get this shield or any UNO shield with this type of UNO USB socket.
Previously I’ve always worked in environments where proper engineers have been designing the hardware (and they weren’t shy about telling me to buzz off and fiddle with the software if I started trying to do their jobs for them)!
