Effects on signal integrity and radiated emission by split reference plane on high-speed multilayer printed circuit boards

Power/ground partitioning has been used to supply multivoltage levels and to isolate power/ground noise in high-speed multilayer printed circuit boards. However, the partitioning of the power/ground plane breaks the current return path of the signal current through either the power plane or the ground plane, which causes undesired effects such as signal distortion, crosstalk, and radiation. To control and suppress these undesired effects, we should understand the electromagnetic mechanism associated with them. In this paper, the mechanism of the reflection and the transmission of the signal by the slotted power/ground plane is well understood through an analysis of measurements based on time-domain reflectometry. Considering the propagation of a slot wave through the slot line on the power/ground plane, we have successfully explained the changes of the transmitted and reflected waveforms. Furthermore, we have numerically and experimentally investigated the effects of the power/ground partitioning on the radiated emission in various structures. Finally, it is confirmed that the employment of a stitching capacitor on the power/ground slot suppresses the signal distortion and the radiated emission significantly. When the size and the location of the stitching capacitor are designed, there should be a compromise between the noise isolation and the guarantee of the return current path, with considering the resonance frequencies of planes by the capacitor.

[1]  S. B. Cohn,et al.  Slot Line on a Dielectric Substrate , 1969 .

[2]  B. Shuppert,et al.  Microstrip/slotline transitions: modeling and experimental investigation , 1988 .

[3]  J. D. Gavenda,et al.  A strip-line TEM cell for measuring electromagnetic emissions , 1991, IEEE 1991 International Symposium on Electromagnetic Compatibility.

[4]  H. Merkelo,et al.  Signal integrity issues at split ground and power planes , 1996, 1996 Proceedings 46th Electronic Components and Technology Conference.

[5]  Gerardo Aguirre,et al.  Methods to reduce radiation from split ground plane structures [packaging] , 1999, IEEE 8th Topical Meeting on Electrical Performance of Electronic Packaging (Cat. No.99TH8412).

[6]  Jun Fan,et al.  RF isolation using power islands in DC power bus design , 1999, 1999 IEEE International Symposium on Electromagnetic Compatability. Symposium Record (Cat. No.99CH36261).

[7]  Y. Ko,et al.  Electromagnetic radiation properties of a printed circuit board with a slot in the ground plane , 1999, 1999 International Symposium on Electromagnetic Compatibility (IEEE Cat. No.99EX147).

[8]  B. J. Rubin,et al.  Distributed effects of a gap in power/ground planes , 1999, IEEE 8th Topical Meeting on Electrical Performance of Electronic Packaging (Cat. No.99TH8412).

[9]  Nanju Na,et al.  Modeling and transient simulation of planes in electronic packages , 2000 .

[10]  Joungho Kim,et al.  Separated role of on-chip and on-PCB decoupling capacitors for reduction of radiated emission on printed circuit board , 2001, 2001 IEEE EMC International Symposium. Symposium Record. International Symposium on Electromagnetic Compatibility (Cat. No.01CH37161).

[11]  Franco Fiori,et al.  Measurement of integrated circuit conducted emissions by using a transverse electromagnetic mode (TEM) cell , 2001 .

[12]  J. R. Miller The impact of split power planes on package performance , 2001, 2001 Proceedings. 51st Electronic Components and Technology Conference (Cat. No.01CH37220).

[13]  Woonghwan Ryu,et al.  Reduction of crosstalk noise in modular jack for high-speed differential signal interconnection , 2001 .

[14]  Joungho Kim,et al.  Microwave frequency crosstalk model of redistribution line patterns on wafer level package , 2001 .

[15]  Junho Lee,et al.  Slot Transmission Line Model of Interconnections Crossing Split Power/Ground Plane on High-speed Multi-layer Board , 2002, Proceedings: 6th IEEE Workshop on Signal Propagation on Interconnects.

[16]  Joungho Kim,et al.  Tapered slot shape on slotted reference plane of multi-layer PCB for reduction of crosstalk and radiated emission , 2002, Electrical Performance of Electronic Packaging,.