Why does the phase difference between the P signal and N signal of differential outputs being non-180 degrees in Agilex™ 7 FPGAs F-Series and I-Series board-level simulations? - Why does the phase difference between the P signal and N signal of differential outputs being non-180 degrees in Agilex™ 7 FPGAs F-Series and I-Series board-level simulations? Description Due to a problem in the Quartus® Prime Pro Edition Software version 24.2 and earlier, non-180 degrees phase shift between the P signal and N signal of differential outputs might be observed in board-level simulations because tdelay values are included in the IBIS model. Resolution To work around this problem, follow these steps: Manually change tdelay_typ , tdelay_min , tdelay_max to NA for all differential output pins in the IBIS file. Restart board-level simulation This problem is fixed beginning with the Quartus® Prime Pro Edition Software version 24.3. Custom Fields values: ['novalue'] Troubleshooting 15016021136 novalue ['novalue'] ['FPGA Dev Tools Quartus® Prime Software Pro'] 24.3 24.2 ['Agilex™ 7 FPGA I-Series', 'Agilex™ 7 FPGA F-Series'] ['novalue'] ['novalue'] ['novalue']