AN 958: Board Design Guidelines

ID 683073
Date 6/26/2023
Document Table of Contents

1.1.2. Select Decoupling CAPS to Meet ZTARGET

To maintain power integrity throughout the entire frequency range of interest, the Power Distribution System relies on the voltage regulator module (VRM), the on-board discrete decoupling capacitors, and inter-plane capacitance (capacitance from the power-ground sandwich in the board stack-up). For the above example, the designer must select these appropriately so that the effective impedance remains below 36.7 Ω within the entire frequency range of interest.

For more details on applying the FDTIM, refer to the PDN Decoupling Calculator Tool and its corresponding User Guide.