一种基于变长数据块相关性统计的测试数据压缩和解压方法

A New Test Data Compression and Decompression Technique Based on Statistic Relativity of Variable Length Data Block

为了解决系统芯片(SoC)测试过程中自动测试设备(ATE)在存储空间以及带宽等方面所面临的问题,本文提出了一种新的基于变长数据块相关性统计的测试数据压缩和解压方法.以测试向量为单位,先用算法确定一个具有最好相关性的数据块作为该向量的参考数据块,再利用它与该向量中数据块的相关性进行压缩.且每个向量的参考数据块长度相互独立.其解压结构只需要一个有限状态机(FSM)、一个5位暂存器和一个与参考数据块等长的循环扫描移位寄存器(CSR)即可,硬件开销小,对ISCAS-89标准电路Mintest集的压缩结果表明,本文提出方案较同类编码方法有更高的压缩效率.

We present a new test data compression and decompression method based on statistic relativity of variable length data block,to resolve the storage and bandwidth problems faced by the automatic test equipment （ATE） in system-on-a-chip （SOC） during test.For each test vector,determine a data block with best relativity to be the referenced data block of it,then compress the vector by the relativity between its data blocks and the referenced data block.Besides,the length of referenced data blocks is independent from each other.Its decompression architecture requires only a finite state machine （FSM）,a five-bit storing device temporarily and a cyclical scan register （CSR） whose length is the same as the referenced data block, so the hardware cost in proposed scheme is small. Experimental results for ISCAS-89 benchmarks show that our new technique can provide a higher compression radios than other compression algorithms.