An impact of layer stack-up on EMI

Author

Radu, S. ; Zeeff, T. ; Nuebel, J. ; Drewniak, J.L. ; Doren, T. P Van ; Hubing, T.H.

Author_Institution

Dept. of Electr. Eng., Missouri Univ., Rolla, MO, USA

Volume

2

fYear

1998

fDate

24-28 Aug 1998

Firstpage

828

Abstract

Investigation of a server shows the heatsink of the CPU module as a primary component of the EMI coupling path. In order to identify the specific noise source and coupling path to the heatsink, a series of experiments were defined to provide support for one source and eliminate others. Based on experiments with two different versions of the CPU module, a stack-up related design guideline is proposed: a ground layer should be the first entire plane (as opposed to V_cc) on the active component side of the board. If there are known IC sources that switch significant currents with the outputs unloaded at nanosecond rise and fall times on both sides of the board, then ground should be the first entire plane on both sides of the board when feasible

Keywords

electromagnetic interference; heat sinks; integrated circuits; printed circuits; switching; CPU module; EMI; EMI coupling path; IC sources; PCB; coupling path; currents switching; heatsink; layer stack-up; primary component; server; specific noise source; Cache memory; Clocks; Electromagnetic compatibility; Electromagnetic heating; Electromagnetic interference; Laboratories; Resistance heating; Solids; Sun; Switches;

fLanguage

English

Publisher

ieee

Conference_Titel

Electromagnetic Compatibility, 1998. 1998 IEEE International Symposium on

Conference_Location

Denver, CO

Print_ISBN

0-7803-5015-4

Type

conf

DOI

10.1109/ISEMC.1998.750314

Filename

750314