本篇論文提出一種新的方式來產生測試資料。主要是藉由內部線性反饋移位暫存器(Internal Linear Feedback Shift Register)所擁有的特性,來達到減少測試時間的目的。最主要是利用每個行(column)所擁有的0和1個數以及分佈的不同,找出能符合特殊架構(Specific Polynomial)的columns,之後利用特殊架構來產生測試資料,剩餘的columns則用傳統的方式產生測試資料。減少測試時間相關的研究,大部分都是利用硬體成本(hardware overhead)來換取測試時間的減少;相對於我的研究則是針對測試資料作分析處理後,根據0和1分佈的不同對掃描鏈(Scan Chain)切割,之後利用SP-LFSR和傳統的LFSR搭配來減少測試的時間,此方法硬體成本只有一些反向器(inverter)以及XOR邏輯閘,因此跟其他方法相比,此方法的hardware overhead相對少許多。
A new test data generation technique, with combining traditional Internal Liner Feedback Shift Register (LFSR) with specific polynomial LFSR, is presented in this work. Specific polynomial LFSR (SP-LFSR) method uses the distribution of number 0 and 1 to find out the columns more having only one “1” in every row. This approach reduces more test time than traditional LFSR one does. Most of previous techniques for reducing test application time require the cost of hardware overhead. In our new method, we analyze the test data and reorder the scan chain into two parts while feeding the test data. As a result, the hardware overhead costs only some inverter and XOR gates.