You are right, 5v should not be used to power the AVR-CAN board. I fixed my post, THANKs.
The on-board regulator that produces the 5v for the board will NOT work if supplied only 5v on its input. It needs about 1.5 volt (or so) more than 5v, so they specify the 7v minimum.
It works at 12v, but the regulator chip gets hot, especially if the board's 5v is ALSO being used to power something else, like a Display and/or an RS232-driven JTAG programmer.
I was told that the regulator chip's input voltage rating is over 15v, but I have not verified this myself. Power dissipation is the larger issue (the regulator getting too hot). So, the LEAF's 12-to-14v supply does seem to work OK, at least for shorter periods of time. But, 7v to 9v is safer, so I now use the 5v zener diode to cut the 12-to14v down to 7-to-9v.
So, the 7v to 9v range is best, I use the $4 switcher 8.4v DC power supply from All Electronics.
See SOC/GID-Meter and CAN-Do Info
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