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Optimising BGA signal routing in PCB designs Posted:02 Feb 2015 Ball grid array  ( BGA ) device packaging is today's standard for housing a range of highly advanced and complex semiconductor devices such as FPGAs and microprocessors. The technology of BGA packaging for embedded designs is steadily advancing to keep up with chipmaker technical advances, with this type of packaging splintering out into standard and micro BGAs. Today, both types deal with increasing numbers of I/Os, and this means signal escape routing is difficult and challenging, even for experienced  printed circuit board  (PCB) and embedded designers. The top job for the embedded designer is to develop appropriate fan-out strategies that won't adversely affect board fabrication. There are several major considerations involved in selecting the correct fan-out/routing strategy: ball pitch, land diameter, number of I/O pins, via types, pad size, trace width and spacing, and the number of layers requ...

December 8, 2014 Single-Electron Transistors A Whole New Way of Switching by Bryon Moyer I love surprises like this. You go into what promises to be a wonky, even dull, conference presentation – and come out agog. That’s exactly what happened to me at the recent ICCAD in San Jose. It was a presentation based on a collaboration between the University of Michigan, Shanghai Jiao Tong University, and National Tsing Hua University about some placement or routing algorithm, but it happened to involve a transistor type that I’d never heard of. And… I don’t know, there was something about the regularity of it, perhaps its elegance, illuminated through a very lucid presentation, that caught my fancy. Heck, even with no prior knowledge, I could actually follow most of the talk. That was exciting enough. Great success! So… what was this thing? It was a way of implementing logic on a fabric of single-electron transistors (SETs). In fact, a reconfigurable fabric. This could be your ...