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Many claim that for stripline, it is ok to cross a split power plane, so long as the other adjacent reference plane is solid. Some others claim if there is an adjacent solid reference plane, less than 5mils away under the split, crosstalk will be mitigated. Read on to see an investigation into what really happens when stripline signals cross split power planes.

The attenuation in a uniform differential pair has two root causes: conductor loss and dielectric loss. By understanding how design decisions affect these two fundamental root causes, we can develop a few simple guiding principles which point us in the right directions to reduce the attenuation of a channel. These are the directions to follow when loss is important. In some cases, increasing the differential impedance will decrease loss, and in some cases it will increase the loss. Read on to see why.

As DDR data transmission rates continue to increase, the signal integrity of the DDR channel has become one of the most critical concerns. This article takes an extensive look at the impact of via stubs on the impedance of the signal lines on DDR4 memory, including test cases and ways to optimize design.

The first goal in any high-speed board stack up design is to engineer interconnects with a target impedance, and the first step in this process is to use a 2D field solver to explore design space with a virtual prototype. Just how well can a field solver predict the impedance of traces on a real board? This article aims to answer this question.

The dielectric constant, Dk, of a laminate will affect the characteristic impedance of a transmission line and its time delay. If you hope to achieve a specific target characteristic impedance on the first pass, it is essential to know the Dk of each laminate layer.  Here is a quick, simple way of measuring it.

It takes only one rogue voltage wave to kill a PDN in high-speed digital designs. Flat impedance optimization before layout lowers the risk of rogue waves occurring in your design. Heidi Barnes explains how rogue waves occur and addresses how to get the best performance at the lowest cost.

What happens when you apply current to a trace? How long until disaster ensues? Douglas Brooks and Johannes Adam melted some boards, turned traces into flames, and applied some equations to shed some light on these questions.

 “A few minutes upfront checking will save you hours of frustration later,” Eric Bogatin explains seven features of s-parameters

Transverse electromagnetic waves are used to transmit the signal between components while PPW waves are used to deliver power to the components. Both waves are useful, but they have to be separated. Yuriy Shlepnev, member of the SIJ Editorial Advisory Board, explains why.