基于单元故障模型的树型加法器的测试

Testing of Tree Adder Based on Cell Fault Model

首先分析了树型加法器的原理 ,总结了其运算特性 .其次在介绍单元故障模型的基础上分析了树型加法器的测试向量生成 .分析结果表明 ,5n - 1个测试向量可以实现树型加法器中所有单元故障的检测 .这些测试向量具有很好的规则性 ,能够利用片上测试向量生成器实现 ,适合于应用内建自测试技术测试 .基于此 ,作者提出了一种内建自测试的测试结构 ,测试时只需存储 7个籽测试向量 ,其它测试向量可以在这 7个籽测试向量的基础上通过循环移位实现 .最后给出了实验分析结果 .

Based on cell fault model, the paper studies test pattern generation and self test of tree adder, which is frequently used in the high performance processors. Firstly, the paper analyzes the tree adder's principle and concludes its properties. Secondly, based on the introduction of cell fault model, which is fit for the testing of regular circuits, the paper presents a complete solution to tree adder testing. In conclusion, 5n-1 test patterns are enough to exhaustedly test all detectable cell faults and any modification of tree adder is not required. Experiment results show that these patterns can guarantee that all cell faults are tested. These patterns have high regularity and can be effectively produced on-chip as required for BIST. Furthermore, a kind of test structure suited for BIST is presented. When testing, only 7 seed patterns are memorized and all other test patterns can be realized by loop shifting.