Hybrid analytical modeling method for split power bus in multilayered package

Abstract

Abstract-As multiple chips are being integrated into a single package with increased operating frequency, switching noise coupling on power buses has become an important design issue. To reduce the noise coupling, a split power bus structure has been generally used in package substrates having multilayered power and ground planes. Consequently, there is an increasing need for an efficient method to analyze a split power bus in a multilayered package. This paper introduces a hybrid analytical modeling method for characterizing a split power bus in a multilayered package. The proposed method uses a resonant cavity model combined with a segmentation method. Furthermore, a port assignment technique and an associated calculation method for the equivalent circuit model parameter of the split gap are proposed. The proposed port assignment technique and the analytical equation make it possible to analyze a split power bus, especially in a multilayered package. To verify the proposed method, multilayered test packages are fabricated and tested by means of frequency-domain measurements. In addition, an optimal power bus design method was successfully demonstrated for suppressing noise coupling between chips on a single package. Finally, the proposed method and optimal power bus design method was verified using a series of frequency-domain and time-domain measurements.Index Terms-Multilayered package substrate, resonant cavity model, segmentation method, simultaneous switching noise (SSN), split power bus.

Modeling and Simulation of Planes With Decoupling Capacitors

“…, α) are divided into β segments that equal the number of modes of the resonant cavity model where Z Ck is the frequency response of the kth capacitor. By KVL and KCL, (8)- (12) are obtained, as shown at the bottom of this page.…”

“…Structure of the power/ground plane with irregular shape. plane in [12] and [13], respectively. The modeling method presented in this paper is extended to model the irregularshaped power/ground plane with decoupling capacitors by using the modeling method for the bare irregular-shaped power/ground plane in [13].…”

Macromodeling of Multilayered Power Distribution Networks Based on Multiconductor Transmission Line Approach

“…Due to the presence of apertures, holes, and irregular geometry of the planes, wraparound currents are supported on the active planes, which lead to the EM coupling between individual planes in the transverse direction [4], [21]. Recent works aimed at quantifying the transverse EM coupling are based on transmission line models for coupling through narrow slots [22] and analytic models based on the Green's function [23]. These models provide a frequency domain solution only and may need an additional post processing like rational curve fitting with passivity enforcement [24]- [25] or numerical convolution [26] for transient analysis.…”

SPICE-Compatible Cavity and Transmission Line Model for Power Bus with Narrow Slots

“…With the aid of the segmentation method, the cavity model can be extended to more general shaped power buses [12]. Recently, several authors proposed lumped circuits to model the coupling effects along two sides of a slot [14], [15]. Comparing with the full-wave approaches, lumped circuit model provides more insights on the physics of coupling and usually takes less computation time.…”