The Stratix II logic and routing architecture

This paper describes the Altera Stratix II™ logic and routing architecture. This architecture features a novel adaptive logic module (ALM) that is based on a 6-LUT, but can be partitioned into two smaller LUTs to efficiently implement circuits containing a range of LUT sizes that arises in conventional synthesis flows. This provides a performance increase of 15% in the Stratix II architecture while reducing area by 2%. The ALM also includes a more powerful arithmetic structure that can perform two bits of arithmetic per ALM, and perform a sum of up to three inputs. The routing fabric adds a new set of fast inputs to the routing multiplexers for another 3% improvement in performance, while other improvements in routing efficiency cause another 6% reduction in area. These changes in combination with other circuit and architecture changes in Stratix II contribute 27% of an overall 51% performance improvement (including architecture and process improvement). The architecture changes red...

• Type: Conference
• Year: 2005
• Where: FPGA
• Authors: David M. Lewis, Elias Ahmed, Gregg Baeckler, Vaughn Betz, Mark Bourgeault, David Cashman, David R. Galloway, Mike Hutton, Christopher Lane, Andy Lee, Paul Leventis, Sandy Marquardt, Cameron McClintock, Ketan Padalia, Bruce Pedersen, Giles Powell, Boris Ratchev, Srinivas Reddy, Jay Schleicher, Kevin Stevens, Richard Yuan, Richard Cliff, Jonathan Rose
• Keywords: FPGA 2005, Hardware, Routing, Stratix II, Stratix II Architecture