跳躍模擬：快速且精確之掃描鏈錯誤診斷技術

Abstract

本論文提出一種新的掃描鏈診斷技術可診斷掃描鏈上的七種單一錯誤，包括兩種黏著性錯誤及五種時間性錯誤。此技術實現跳躍模擬─一種新穎的平行模擬技術─此技術能快速找出錯誤分子的上邊界及下邊界。無論掃描鏈長度為何，跳躍模擬能將多次模擬一次完成，因此模擬時間相當短。此外，跳躍模擬藉由觀察被大多數診斷技術忽略的主要電路數據輸出及掃描鏈數據輸出來縮小錯誤分子的範圍。在ISCAS’89基準電路的實驗顯示，平均而言，跳躍模擬只需三個錯誤圖樣將錯誤分子範圍縮小至十個以下。當錯誤的資料被截短因為被測試機台記憶體限制時，此技術依然相當有效診斷電路。

This thesis presents a scan chain diagnosis technique to locate seven types of single faults in scan chains, including two single stuck-at faults and five single timing faults. This technique implements the Jump Simulation, a novel parallel simulation technique, to quickly search for the upper and lower bounds of the fault. Regardless of the scan chain length, Jump Simulation packs multiple simulations into one so the simulation time is short. In addition, Jump Simulation tightens the bounds by observing the primary outputs and scan outputs of good chains, which are ignored by most previous techniques. Experiments on ISCAS’89 benchmark circuits show that, on the average, only three failure patterns are needed to locate faults within ten scan cells. The proposed technique is still very effective when failure data is truncated due to limited ATE memory.