ORCA: a high speed, high density FPGA architecture

Abstract

The Optimized Reconfigurable Cell Array (ORCA) is an SRAM-based field programmable gate array (FPGA) architecture that makes FPGAs attractive in applications that were previously reserved for gate arrays. The ORCA has an architecture that assures dense layouts of all major types of functionality needed, including data path, random logic, and SRAM. The ORCA FPGA utilizes a novel approach to routing interconnect to achieve a 40% to 100% increase in density over traditional SRAM-based FPGA architectures. The resulting compaction of logic functions into fewer programmable logic cells coupled with dedicated fast arithmetic circuits permits system clock rates of 80 MHz. The ORCA software was designed in parallel with the architecture to insure that all of the benefits of the architecture would be accessible to users through the algorithms of the software. This eliminates the need for users to obtain a detailed knowledge of the architecture in order to use it efficiently. Instead, high-density, high-speed designs are produced automatically by software, with virtually no need for manual intervention on the part of the user. >