Open Access. Powered by Scholars. Published by Universities.®
Electrical and Computer Engineering
Electrical and Computer Engineering Faculty Research & Creative Works
Articles 1 - 4 of 4
Full-Text Articles in Engineering
Dc Power-Bus Design Using Fdtd Modeling With Dispersive Media And Surface Mount Technology Components, Xiaoning Ye, Marina Koledintseva, Min Li, James L. Drewniak
Dc Power-Bus Design Using Fdtd Modeling With Dispersive Media And Surface Mount Technology Components, Xiaoning Ye, Marina Koledintseva, Min Li, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
DC power-bus modeling in high-speed digital design using the finite-difference time-domain (FDTD) method is demonstrated herein. The dispersive character of the dielectric layers used in printed circuit board substrates is taken into account in this study. In particular, FR-4 is considered. The complex permittivity of the dielectric is approximated by a Debye model. A wide-band frequency response (100 MHz-5 GHz) is obtained through a single FDTD simulation. Good agreement is achieved between the modeled and measured results for a typical dc power-bus structure with multiple surface mount technology (SMT) decoupling capacitors placed on the printed circuit board (PCB). The FDTD …
The Effects Of Via Transitions On Differential Signals, Chen Wang, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander, James L. Drewniak
The Effects Of Via Transitions On Differential Signals, Chen Wang, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
Vias in differential transmission lines have been modeled using the finite-difference time-domain (FDTD) method. The velocity that the differential signal propagated through the vias was estimated. Differential S-parameters were calculated up to 50 GHz. Below 10 GHz, the differential signal can propagate through vias without much reflection and distortion. However, as frequency increases, the reflection from the vias and the loss of differential power become significant.
Grounding Of Heatpipe/Heatspreader And Heatsink Structures For Emi Mitigation, Chen Wang, James L. Drewniak, D. Wang, Ray Alexander, James L. Knighten, David M. Hockanson
Grounding Of Heatpipe/Heatspreader And Heatsink Structures For Emi Mitigation, Chen Wang, James L. Drewniak, D. Wang, Ray Alexander, James L. Knighten, David M. Hockanson
Electrical and Computer Engineering Faculty Research & Creative Works
EMI problems caused by the presence of heatpipe/heatspreader and heatsink structures in a high-speed design are well known in engineering practice. High-frequency noise can be coupled from IC packages to an electrically conductive heatsink or heatspreader attached to the IC, which then is radiated, or the energy coupled to an enclosure cavity mode. This EMI coupling path was modeled with the finite-difference time-domain (FDTD) method, and a mitigation approach was investigated. Good agreement between measurements and FDTD modeling is demonstrated, indicating FDTD is a suitable tool for analysis and design. Then, several grounding schemes suitable for a heatsink or heatspreader …
Investigation Of Pcb Layout Parasitics In Emi Filtering Of I/O Lines, Xiaoning Ye, Geping Liu, James L. Drewniak
Investigation Of Pcb Layout Parasitics In Emi Filtering Of I/O Lines, Xiaoning Ye, Geping Liu, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
EMI filters are often utilized on I/O lines to reduce high-frequency noise from being conducted or coupled off the PCB and resulting in an EMI problem. However, layout parasitics are usually inevitable in practical circuit design, and the filtering performance may vary. In this study, the impact of the board layout on the filtering performance is investigated by |S21| measurements of sample PCB boards with different filter layouts. The finite-difference time-domain method is applied to model the boards, support the experimental work, and can be used to provide a means for conducting "what-if" engineering studies.