With the growing density and shrinking feature size of modern semiconductors, it is increasingly difficult to manufacture defect free semiconductors that maintain acceptable levels of reliability for long periods of time. These systems are increasingly susceptible to wear-out by failing to meet their operational specifications for an extended period of time. The reconfigurability of FPGAs can be used to repair post-manufacturing faults by configuring the FPGA to avoid a damaged resource. This thesis presents a method for preemptively preparing to repair FPGA devices with wear-out faults by precomputing a set of repair circuits that, collectively, can repair a fault found in any logic block of the FPGA. This approach relies on logic placement and routing to create “repair” circuits that avoid specific logic blocks. These repairs can be used when a specific resource has failed. New placement and routing algorithms are proposed for generating such repair circuits. The number of repairs needed to create a complete repair set depends heavily on the utilization of the FPGA resources. The algorithms are tested against several benchmarks and with multiple area constraints for each benchmark. Using this work, on average 20 repair configurations were needed to repair 99% of permanent faults.
College and Department
Ira A. Fulton College of Engineering and Technology; Electrical and Computer Engineering
BYU ScholarsArchive Citation
Jensen, Joshua E., "Preemptive Placement and Routing for In-Field FPGA Repair" (2015). All Theses and Dissertations. 4417.
FPGA, Repair, Fault-Tolerance, Placement, Routing