Time-Multiplexed Compressed Test of SOC Designs

In this paper we observe that the necessary amount of compressed test data transferred from the tester to the embedded cores in a system-on-a-chip (SOC) varies significantly during the testing process. This motivates a novel approach to compressed system-on-a-chip testing based on time-multiplexing the tester channels. It is shown how the introduction of a few control channels will enable the sharing of data channels, on which compressed seeds are passed to every embedded core. Through the use of modular and scalable hardware for on-chip test control and test data decompression, we define a new algorithmic framework for test data compression that is applicable to system-on-a-chip devices comprising intellectual property-protected blocks.