Device-Specific Power Delivery Network (PDN) Tool 2.0 User Guide
ID
683293
Date
8/24/2021
Public
1.2.2.1.1. Device Selection Section
1.2.2.1.2. Power Rail Data and Configuration Section
1.2.2.1.3. Meeting Target Impedance when Entering 0 A into the PDN Tool
1.2.2.1.4. Dealing with Multiple Shared Power Supply Pin Types
1.2.2.1.5. VRM Data Section
1.2.2.1.6. Rail Group Summary Section
1.2.2.1.7. VRM Impedance Section
1.2.2.1.8. BGA Via Section
1.2.2.1.9. Plane Section
1.2.2.1.10. Spreading Section
1.2.2.1.11. Implementing Split Planes
1.2.2.1.12. FEFFECTIVE Section
1.2.2.1.13. Decoupling Section
1.2.2.1.14. Results Summary Section
1.2.2.1.15. Recommended Flow for Deriving Decoupling for an FPGA System using the System_Decap Tab
1.3.2.2. Rail Group Summary
The PDN tool automatically calculates the target impedance (ZTARGET) based on the recommended Dynamic Current Change% and Noise Tolerance%.
Figure 25. Rail Group SummaryBoxes shaded in light blue are drop-down menus with different options to select. Core Clock Frequency and Current Ramp Up Period options vary depending on your design.

With these options enabled, the ZTARGET curve relaxes from certain frequencies based on the inputs.
Figure 26. Flat versus Curved ZTARGET
