Multi-Objective Optimization of Decoupling Capacitors for Placement and Component Value

A multiobjective evolutionary method is proposed for the optimization of surface mount device (SMD) multi-layer ceramic chip (MLCC) capacitors used for decoupling on printed circuit boards (PCBs) with resonant power-ground plane pairs. The proposed approach provides options for designers to meet power integrity specifications by employing uniform-valued capacitors that help to reduce the bill-of-material (BOM) cost and mitigate the part procurement risk. It is also shown that uniform MLCC capacitors with variable distance from power pins can have a similar decoupling effect to an assortment of capacitors. By simultaneously optimizing the pin-capacitor distance and value, the proposed method is shown to allow for the allocation of fewer decoupling capacitors under the ball-grid-array (BGA) pin field of an integrated circuit (IC) device.