A hybrid scheme for compacting test responses with unknown values

This paper presents a hybrid compaction scheme for test responses containing unknown values, which consists of a space compactor and an unknown-blocking Multiple Input Signature Registers (MISR). The proposed scheme guarantees no coverage loss for the modeled faults. The proposed hybrid scheme can also be tuned to observe any userspecified percentage of responses for controlling the coverage loss for un-modeled faults. The experimental results demonstrate that, in comparison with a space compactor or an unknown-blocking MISR alone, the hybrid compaction scheme achieves a lower coverage loss without demanding more test-data volume. In addition, we propose a quantitative approach to estimate the required percentage of observable responses for the proposed scheme, directly based on a test-quality metric of un-modeled faults.

• Type: Conference
• Year: 2007
• Where: ICCAD
• Authors: Mango Chia-Tso Chao, Kwang-Ting Cheng, Seongmoon Wang, Srimat T. Chakradhar, Wenlong Wei
• Keywords: Hardware, Hybrid Compaction Scheme, Hybrid Scheme, ICCAD 2007, Scheme Guarantees