Board power bus decoupling using embedded capacitance

The purpose of decoupling capacitors on printed circuit boards is to meet the instantaneous current demands of high-speed active devices while minimizing power bus noise. Embedded capacitance is an alternative to discrete decoupling capacitors and is achieved by taking advantage of the natural capacitance between the power and ground planes. This paper investigates the electrical properties of boards manufactured with four different kinds of embedded capacitance. These boards have powerground plane pairs separated by very thin materials with high dielectric constants. It is shown that some kinds of embedded capacitance work significantly better than standard decoupling schemes using discrete decoupling capacitors.