在廣播壓縮環境下應用偏移插入技術之壓縮感知自動化測試圖樣產生技術

Compression-aware Automatic Test Pattern Generation based on Skew Insertion Technique in the Broadcast Environment

林建儒(Chien-Ju Lin)

指導教授 ： 黃俊郎

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00817

摘要

隨著積體電路製造技術的演進，設計益趨複雜，造成大量測試圖樣及測試機台成本的增加，測試資料壓縮已成為必要的技術。過去有許多研究藉由重新最佳化排序掃描鏈的廣播式壓縮技術來解決這個問題。然而，將掃描鏈重新排序會影響積體電路的時序及增加繞線的負擔。
偏移插入技術提供了另外一種解決方法的選擇。在掃描鏈之前插入偏移的硬體來延遲收到的測試資料值，以將測試資料變成可用廣播壓縮環境來編碼。然而過去此類方法通常分析操作事先產生的測試資料，使得已被廣泛應用的動態壓縮技術不能再被使用來增加壓縮率。此外，如果找不到可編碼的測試圖樣，則額外需要的序列圖樣會大幅降低壓縮率。
本篇論文在自動測試圖樣產生的同時，決定可被編碼組態，如此一來可以及早迴避矛盾的賦值。核心技術是能夠考慮壓縮的自動測試圖樣產生技術，以及部分序列式技術來減輕由廣播式壓縮造成的高度線性相關限制。
實驗中使用ISCAS89及ITC99標準電路來驗證本篇論文所提出的技術之效能。此技術基本上能夠提供高壓縮率，且不需要最佳化掃描鏈排序。

關鍵字

壓縮感知 ； 自動測試資料產生 ； 偏移插入 ； 廣播式測試資料壓縮 ； 掃描鏈測試

並列摘要

As the advance of the technology and the design complexity increases, test compression techniques has become mandatory due to the growing test data volume and high ATE test cost. Several broadcast based technique has been proposed to address this issue by reordering the scan chains into an optimal structure. However, the reordering of the scan chains generally impact the timing and increases routing overhead.
Skew insertion provides an alternative solution. By inserting skews in front of the scan chains to delay the value received, the test patterns become encodable in the broadcast environment. However, conventional methods usually manipulate on the pre generated test sets, thus the widely-adopted dynamic compaction technique cannot be utilized afterward to further increase the compression ratio. Moreover, if an encodable solution cannot be found, the additional topping serial pattern will greatly degrades the compression ratio.
This thesis determines the encodable skew configuration during ATPG, so as to avoid the conflict assignment in an early stage. The core technology is the compression aware ATPG, and the partial serial technique is further proposed to alleviate the high linear dependency of the broadcast constraints.
Effectiveness of the proposed technique is validated with ISCAS89 and ITC99 benchmark circuit. The proposed technique generally provide high data reduction ratio, and without the need of the reordering the scan chains.

並列關鍵字

Compression-aware ； Automatic Test Pattern Generation ； Skew Insertion ； Broadcast test data compression ； Scan testing

參考文獻

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