Recommended Decoupling Capacitor Quantities for Versal Devices - UG863

Versal Adaptive SoC PCB Design User Guide (UG863)
Document ID
UG863
Release Date
2025-05-21
Revision
1.10 English

Recommended decoupling quantities for core, auxiliary, and VCCO rails in Versal devices can be obtained via the PDM tool. The PDM tool provides a custom set of decoupling guidelines based on the actual usage parameters of the design. Recommend decoupling capacitor values and manufacturers are listed in PDM. The ESR and ESL values are also listed to allow for selection of equivalent capacitors based on availability and the user's application requirements. It is recommended to validate the power decoupling network with a board level S- parameter simulation.

Note: Each decoupling capacitor is chosen to cover an approximate frequency range centered around the self-resonant frequency of the capacitor. The effective frequency range is determined by the number of capacitors of a given type, which is chosen by the PDM tool based on the power needs of the design. The self-resonant frequency for each capacitor can be seen in the PDM tool by hovering over the capacitor value in the Power Delivery Design tab.

The following sections illustrate the methodology that the PDM tool uses for determining the appropriate number of decoupling capacitors to use for a particular power rail.