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I'm newbie as user of FPGA DE0-nano.
I want to ask, if connected external circuit to FPGA DE0-nano board, what must to be noted in order to FPGA board aware of destruction ?
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1. The DE0-nano pins are 3.3V and have no protection for over-voltage. Make sure you only connect 3.3V signals to the I/O headers.
2. Connect the ground on the DE0-nano to the ground on your external circuit so that you have a common reference ground.
3. If your external circuit is powered by the DE0-nano, then make sure not to violate the USB current draw.
Cheers,
Dave