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I'm using the Cyclone II FPGA Starter Development Kit and until now I've been using the 7.5V power adapter but now I want to put it in box with other equipment.
It looks like there are 5V regulators on the board so am I same using a 15V or 12V power supply instead?
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Look at the schematic. Check the input capacitor voltage rating and if there is a TVS on the input.
If the power supplies are switch-mode power supplies, then check they are rated to operate at above the voltage you plan to use.
If the power supplies are linear regulators, then you will be increasing the voltage drop across those parts, and increasing their power dissipation. I would not recommend increasing the external power rail in that case, without careful analysis of the heating.
Cheers,
Dave
