Partial Core Encryption for Performance-Efficient Test of SOCs

The isolation of a core through full I/O scan helps ease SOC test challenges;yet the performance of high-speed SOCs is significantly hampered.We propose a partial core encryption methodology wherein thecore vendor unveils only a small part of the core logic, successfully satisfyingcore IP protection requirements. Once the partially encryptedcores are merged into an SOC, the system integrator performs test generationon the visible SOC logic only, greatly reducing the test generationeffort expended. By utilizing the test data provided by the core vendoras well, the SOC integrator can test the SOC with no performancedegradation. We present an efficient fault analysis based core encryptionalgorithm which is guided by judiciously computed testability measures.The experimental results confirm the significantly high encryption levelsattained by the proposed encryption algorithm.