基于位跳变相容的多扫描链压缩方法

Multiple scan chains compression method based on bit-transition compatibility

通过对数据块进行相容性分析发现,大多数数据块之间的不相容只是由于其中极少部分的对应位不相容导致的。针对这种情况,本文提出了一种基于跳变位相容的测试数据压缩方法,将这些数据块归入同一组中,用同一个Huffman码字来表示,并用字典编码来表示这些跳变位在数据块中的位置,从而提高短码字数据块的出现频率和减少不能采用码字编码的数据块个数,进而提高压缩率。基于ISCAS-89标准电路的实验结果与已有的传统的Selective Huffman编码技术相比,本方案的压缩率平均提高了12.18%,最大压缩率达到了92.55%。

Analysis of the data block compatibility finds that some data blocks of the test data are incompatible just because of very small part of incompatible corresponding bits.In response to this situation,the paper proposes a novel test data compression technique using bit-transition compatibility,which put these data blocks in the same group,used the same Huffman code word to be indicated,and used a dictionary encoding to indicate the bit transition positions in the data blocks.Therefore,it can enhance the frequency of the data blocks encoded by short code word and reduced the number of the data blocks not encoded so that it provides a substantial improvement in the compression ratio.The experimental results based on ISCAS-89 benchmark circuits and compared our results with existing Selective Huffman-based compression techniques,our algorithm outperforms by up to 12.18%,giving a best possible test compression of 92.55%.