Daniel Douriet

Crosstalk Analysis between Interconnects in High-Speed Server Packages

This paper discusses crosstalk analysis between interconnects in high-speed server packages. Over the last decade, the scaling of the CMOS transistors has enabled the design of microprocessors operating at multi-gigahertz frequencies. For meeting the high bandwidth demands and low-power requirements, digital technologies are quickly moving to gigabit data rate and sub-voltage range signaling levels. However, this higher speed performance comes at a price, which means that signal integrity becomes a significant portion of the design effort. Especially, crosstalk analysis between interconnects in high-speed packages has become critical for design optimization of signal interconnects in system. This paper investigates importance of crosstalk analysis for IBMs high-speed server packages. For an efficient crosstalk analysis between interconnects in highspeed digital systems, an IBMs internal tool called PATS (package analysis tool suite) was used to investigate crosstalk over 1000 signal nets. The ISNRR (integral of squared noise ramp response) method has been developed to quantify crosstalk accurately and used to analyze IBMs organic modules for high-speed applications.

Package and Printed Circuit Board Design of a 19.2 Gb/s Data Link for High-Performance Computing

A 19.2 Gb/s per lane link with IBMs latest POWER8 processor module has been analyzed. This paper presents the overview of the high-speed link design from the signal integrity point of view. Design approaches in package and printed circuit board (PCB) to support the target data-rate have been discussed. The end-to-end communication bus is modeled from extracted post-route design with a 3-D full-wave extractor and has been simulated with IO properties at system level. Bath-tub curves are generated from data gathered in functioning systems running this 19.2 Gb/s link to confirm the operation of the link meets the required bit-error-rate criteria as the modeling and simulation predicted.