Prediction of compression bound and optimization of compression architecture for linear decompression-based schemes
On-chip linear decompression-based schemes have been widely adopted by industrial circuits nowadays to effectively reduce the ever increasing test data volume and test time. Though they can easily achieve relatively high compression ratio, there is a bound of effective compression ratio for these compression schemes. Prior work tried to address this problem by trying different compression architectures to identify this compression bound. However, they can not predict this compression bound efficiently. In this paper, we will first analyze the correlation between the effective compression ratio and the compression architecture, thus to predict that compression bound efficiently. In addition, this paper will also propose how to design the compression architecture for target effective compression ratio with one-pass calculation, which was usually done by a time-consuming try-and-error process as well in the current DFT flow. Experimental results show the accuracy of the prediction and the effectiveness of the compression architecture design.