An Initialization Process to Support Online Testing Based on Output Comparison for Identical Finite-State Machines

作者：Pomeranz Irith^*

来源：IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, 2018, 37(7): 1494-1504.

DOI：10.1109/TCAD.2017.2750060

• Fault detection
• finite-state machines
• online testing
• synchronization

Identical instances of a logic block are included in a design to improve its performance or reliability. This allows instances at close proximity to be tested by comparing their output responses, alleviating the need to know which tests will be applied, or what the fault-free response is. This paper considers an approach to online testing where the primary output sequences of identical finite-state machines that receive the same primary input sequences are compared to detect faults. To address the hardware and delay overheads of bringing one of the machines to the same state as the other before starting the output comparison process, this paper describes an initialization process where only part of the state of one machine is loaded into the other, and subsequences of their common primary input sequences are used for completing the initialization process. A unique feature of this process is that it addresses the situation where the input sequences that are applied during online testing, and the initial state for output comparison, are unknown. With this initialization process it is possible to start the output comparison process at an arbitrary point during functional operation. Experimental results for benchmark circuits demonstrate the percentages of state variables who values need to be loaded from one machine to the other, the fault coverage that can be achieved by output comparison following initialization, and the occurrence of failures in the initialization process.

• 出版日期2018-7