Behind the Design: Seagate

This is the second post in a series showcasing the winners of the 2014 Technology Leadership Awards. View the first here.

First place winner in the Computers, Blade & Servers, and Memory Systems category: Seagate Technology, United States.

Design: The team used all of the “tricks in the book” to achieve placement and routing within the speed/timing parameters on their mid-range enterprise solid-state drive.

Design team:

• Andre’ Dutko, Keith MacLean

Design challenges:

• This was a heavily constrained design with a high percentage of high-speed nets; over 64,000 constraints in the design and lots of restrictions due to PCIE, DDR3 and Flash. Tight length matching to balance byte lanes; isolation of multi-GHz signals; layer count and thickness restrictions.
• Adjacent layer coupling and reference plane impact on SI required extensive collaboration between layout designer and project engineer.
• Power distribution for 37 voltages with current ranging from 0.5 – 5.0 amps.
• Buried vias were avoided as a cost consideration.

Design tools and team comments:

• Xpedition® Enterprise flow and Hyperlynx®
• The 556 pin BGA/SOC was the most complex component. Beyond the multiple power supplies required, it is driving two DDR3 chips and 16 (back-to-back) NANDs. All of which had separate byte lanes containing unique Data, Command and Control and/or Address.
• High volume manufacturing requirements with multiple variants also added to cost considerations.

Judges’ comments:

• This design has very high lead density due to innovative side-side placement and routing of the memory.
• This is a tight design considering that is utilizes standard technology instead of HDI. I like the way they utilized the various tools within the flow to achieve design requirements.

About the Technology Leadership Awards

Started in 1988, this program is the longest running competition of its kind in the electronic design automation (EDA) industry. It recognizes engineers and designers who use innovative methods and design tools to address today’s complex PCB systems design challenges and produce industry-leading products. See the full list of 2014 winners here.