Felipe

Hi @JColvin I recently started working with two boards, a Nexys 4 DDR and a Nexys A7, because they provide access to the different voltage levels necessary for the correct operation of the board. My goal is to perform a voltage characterization of my design with variations in the FPGA core power supply (1V +-0.05), but so far I have not been able to power up the board using the test pins as inputs. When I make the connections shown in the modified schematic in the first attached figure ( always keeping disabled the switch (sw16) to avoid enabling the ADP devices shown in the second attached figure), I can't program it via Vitis, neither get the Vivado Hardware Manager to recognize the FPGA, so I can't program it. I would like to know if I can receive your support (or if you can refer anyone in this matter) regarding this characterization, first confirming that the test pins can be used to perform the voltage characterization on these boards; and second, what would be the correct way to perform this voltage characterization process on the FPGA core for these boards. Thank you very much in advance, and I remain attentive to your response. Best regards, Felipe.