多掃瞄鏈之測試資料壓縮經由可變動切片方式

Data Compression for Multiple Scan Slices Using Slice Run Length

楊正旗(Cheng-Chi Yang)

指導教授 ： 曾王道

元智大學/資訊學院/資訊工程學系/碩士(2009年)

https://doi.org/10.6838/YZU.2009.00278

摘要

在本篇論文中我們提出一種可以有效減少工業用測試資料的方法，來面對越來越龐大的測試資料。有別於以往multiple scan chains的壓縮方式，我們提出的方法不是單純的只針對每筆slice做處理，更是結合了run length技巧。所提出的方法不需要動到任何CUT的內部架構，也不需要特定的演算法，我們只利用在slice中極少數的specified bits。因此其壓縮率是依據specified bits在slice中分散的密度決定。編碼也不同於一般的編碼方式， codeword的長度是不固定的，而是根據不同的參數來調整壓縮率以及編碼的長度。我們的硬體架構很簡單，只需要簡單的buffer、decoder及數個counter即可。最後從實驗結果中可以發現，隨著電路的增大，如我們一開始預期般的一樣，其效率會越明顯，這是在multiple slices的效用有展現出來。

關鍵字

切片 ； 可變動切片方式 ； 多掃瞄鏈

並列摘要

In this thesis, we proposed an effective compression method to reduce large amounts of test data volume for multiple-scan testing. Different from other compression methods using multiple scan chains, in this method, we not only deal with each slice but also combine the run-length-based technique. There is no need to change the internal structure of CUT, nor do we use a particular algorithm. Only a few specified bits in each slice are exploited. Hence, the compression ratio is decided according to the specified bits density in each slice. Our code is quite different; the length of each codeword is not fixed. We will follow different parameters to adjust the compression ratio and the length of each codeword. Our hardware structure is simple, only a buffer, decoder and several counters are needed. Finally, experiment results show, our method is especially effective as the circuit size grows.

並列關鍵字

Scan Slice ； Slice Run Length ； Multiple Scan Chain

參考文獻

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