Time-Multiplexed Online Checking: A Feasibility Study

There is growing demand for online hardware checking capability to cope with increasing in-field failures resulting from variability and reliability problems. While many online checking schemes have been proposed, their area overhead remains too high for cost-sensitive applications. We introduce a time-multiplexed online checking scheme using embedded field-programmable blocks for checker implementation, which enables various system parts to be checked dynamically in-field in a time-multiplexed fashion. This incurs less area overhead, and could maintain fault coverage similar to traditional checkers. The test quality is studied using a probabilistic model. The implementation feasibility using a field-programmable gate array (FPGA) is demonstrated.