Decoupling with Embedded Capacitors

摘要

In a previous article ("Decoupling with Surface Mount Capacitors," CircuiTree, June 2003), we described what decoupling is and how it's done on PWBs today. In this article, we'll provide a brief summary of the technical reasons that make embedded caps more attractive for this than surface mount, followed by an overview of what's becoming available commercially for you to use. The overall conclusion is going to be that the decoupling caps scattered over the board should be embedded based on cost considerations, while the close-in caps, those grouped around individual chips, should be replaced on performance considerations―lower inductance.