This table shows the core voltage for some popular Altera and Xilinx FPGAs. It is important to note that even within the same family of FPGAs, there are different specifications depending on speed grades and feature set. For details, refer to the FPGA’s datasheet. Note that the tolerance range holds true even when transients occur. Care is required in choosing and designing a voltage regulator to ensure the FPGA is not damaged by any excursions.