[Show abstract][Hide abstract] ABSTRACT: Differential lines are extensively used in high-speed digital circuits due to their ability to improve signal integrity by rejecting common-mode noise. However noise is injected into differential signals when there are irregularities in the signaling setup. These anomalies may be via transitions of differential lines through power planes in power distribution systems, via stubs, asymmetric lengths of differential lines, different transition points for each of the differential vias etc. This paper quantifies noise due to irregular differential structures in frequency domain. Presence of noise in differential signaling is verified through a set of test vehicles. The effect of signal to power coupling from differential lines on signal jitter is also investigated.
Electronic Components and Technology Conference, 2008. ECTC 2008. 58th; 06/2008
[Show abstract][Hide abstract] ABSTRACT: The coupling of simultaneous switching noise (SSN) in mixed signal system on package modules is a critical signal and power integrity (SI/PI) problem. In the presence of split planes and apertures, SSN coupling occurs both horizontally as well as vertically across layers. Thus, to catch SI and PI problems at an early stage of design requires fast signal and power co-simulation methodologies. In this paper, we outline the multi-layer finite difference method and how the accuracy of the technique can be enhanced with models for fringe and gap effects. We then briefly describe a method for integrating the signal distribution network with the power distribution network to enable co-simulation. The method is then applied to a mixed signal board containing split planes, and numerical results are compared to full-wave simulations.
Electromagnetic Compatibility, 2007. EMC 2007. IEEE International Symposium on; 08/2007
[Show abstract][Hide abstract] ABSTRACT: Packages for modern mixed signal systems in package (SiP) require split planes and power islands to isolate multiple power supplies. To reduce design iterations due to signal integrity issues, the frequency response of the package needs to be obtained accurately at an early stage of the design. Full-wave EM solvers are generally the most accurate tools available. However, the high time and memory required by such tools relegates their use to final verification, at which stage design iterations are expensive. The finite difference method has been shown to be efficient in simulating single plane-pair structures with slots as long as one plane is completely solid. Also, the multilayer finite difference method (M-FDM) can accurately model multilayer structures with apertures, so long as there are no power islands. In this paper, a formulation for efficient simulation of multilayer structures with split planes has been investigated. Further, a method by which transmission lines can be integrated with a power distribution network containing apertures and split planes has been discussed. The formulation has been validated by comparing results with full-wave EM simulations.