Fault-Tolerant Techniques to Manage Yield and Power Constraints in Network-on-Chip Interconnections

The use of fault-tolerant mechanism is essential to ensure the correct functionality of integrated circuits after manufacturing due to the massive number of faults that may occur during the process. In this work, we propose a set of fault-tolerant techniques to cope with faulty wires in Network-on-Chip (NoC). The most appropriate technique is chosen by taking into account the number of faulty wires and their location in the NoC. The goal is to combine different techniques to reduce overheads in area, delay and power. The use of testing and diagnosis can minimize costs associated with embedded faulttolerant mechanisms once the architecture adapts itself to work in different faulty scenarios. The proposed fault-tolerant strategy uses a lightweight adaptive routing combined with data splitting, which is able to send the data in one clock cycle. The power penalty has a low correlation with the number of faulty interconnections. Results for MPEG4 and VOPD applications running on the NoC with different faulty case-study scenarios show that the proposed techniques can tolerate many faulty interconnections with a low area, performance and power overheads.