Low-Capture-Power Test Generation for Scan-Based At-Speed Testing

Scan-based at-speed testing is a key technology to guarantee timing-related test quality in the deep submicron era. However, its applicability is being severely challenged since significant yield loss may occur from circuit malfunction due to excessive IR drop caused by high power dissipation when a test response is captured. This paper addresses this critical problem with a novel low-capture-power X-filling method of assigning 0\u27s and 1\u27s to unspecified (X) bits in a test cube obtained during ATPG. This method reduces the circuit switching activity in capture mode and can be easily incorporated into any test generation flow to achieve capture power reduction without any area, timing, or fault coverage impact. Test vectors generated with this practical method greatly improve the applicability of scan-based at-speed testing by reducing the risk of test yield lossIEEE International Conference on Test, 2005, 8 November 2005, Austin, TX, US

A Closed System for Pico-Liter Order Substance Transport from a Giant Liposome to a Cell

In single cell analysis, transport of foreign substances into a cell is an important technique. In particular, for accurate analysis, a method to transport a small amount (pico-liter order) of substance into the cell without leakage while retaining the cell shape is essential. Because the fusion of the cell and the giant liposome is a closed system to the outside, it may be possible to transport a precise, small amount of substances into the cell. Additionally, there is no possibility that a leaked substance would affect other systems. To develop the liposome-cell transportation system, knowledge about the behavior of substances in the liposome and the cell is important. However, only a few studies have observed the substance transport between a liposome and a cell. Here, we report observation of small amount of substance transport into a single C2C12 cell by using a giant liposome. Substance transport occurred by electrofusion between the cell and the giant liposome containing the substance, which is a closed system. First, to observe the electrofusion and substance transport from the moment of voltage application, we fabricated a microfluidic device equipped with electrodes. We introduced suspensions of cells and liposomes into the microfluidic device and applied alternating current (AC) and direct current (DC) voltages for electrofusion. We observed a small amount (22.4 ± 0.1%, 10.3 ± 0.4% and 9.1 ± 0.1%) of fluorescent substance (Calcein) contained in the liposomes was transported into the cell without leakage outside the cell, and we obtained the diffusion coefficient of Calcein in the cell as 137 ± 18 μm2/s. We anticipate that this system and the knowledge acquired will contribute to future realization of more accurate single cell analysis in a wide range of fields

A framework of high-quality transition fault ATPG for scan circuits

ABSTRACT This paper presents a framework of high-quality test generation for transition faults in full scan circuits. This work assumes a restricted broad-side testing as a test application method for two-pattern tests where control of primary inputs and observation of primary outputs are restricted. Because we use a modified time expansion model of a circuit-under-test during ATPG and fault simulation, conventional ATPG and fault simulation programs can work with minor change. The proposed ATPG method consists of two algorithms, which are activation-first and propagation-first, and for each fault it is decided which algorithm should be applied. Test patterns are generated such that transition faults with small delay can be detected, i.e. a path for fault excitation and propagation becomes as long as possible. In experimental results we evaluate test patterns generated by the proposed method using SDQM that calculates delay test quality, and show the effectiveness of the proposed method

Estimation of Delay Test Quality and Its Application to Test Generation

As a method to evaluate delay test quality of test patterns, SDQM (Statistical Delay Quality Model) has been proposed for transition faults. In order to derive better test quality by SDQM, the following two things are important: for each transition fault, (1) to find out the accurate length of the longest sensitizable paths along which the fault is activated and propagated, and (2) to generate a test pattern that detects the fault through as long paths as possible. In this paper, we propose a method to calculate the length of the potentially sensitizable longest path for detection of a transition fault. In addition, we develop a procedure to extract path information that helps high quality transition ATPG. Experimental results show that the proposed method improves SDQL (Statistical Delay Quality Level) by not only accurate calculation of the longest sensitizable paths but also detection of faults through longer paths

A case of endometriotic cyst enlargement during pregnancy owing to desmoplasia and rupture at 36 weeks of gestation

Decidualized ovarian endometrioma is a rare phenomenon that occurs during pregnancy. A 43-year-old pregnant woman with an endometriotic cyst increased owing to desmoplasia presented to us urgently with abdominal pain and was performed a cesarean section at 36 weeks and 1 day of pregnancy. The left ovarian cyst was noted to be partially ruptured, and the pathological diagnosis was an endometriotic cyst with desmoplasia. Endometriotic cysts may enlarge during pregnancy owing to desmoplasia and rupture in the last trimester of pregnancy, causing acute abdomen

Estimation of Delay Test Quality and Its Application to Test Generation

As a method to evaluate delay test quality of test patterns, SDQM (Statistical Delay Quality Model) has been proposed for transition faults. In order to derive better test quality by SDQM, the following two things are important: for each transition fault, (1) to find out the accurate length of the longest sensitizable paths along which the fault is activated and propagated, and (2) to generate a test pattern that detects the fault through as long paths as possible. In this paper, we propose a method to calculate the length of the potentially sensitizable longest path for detection of a transition fault. In addition, we develop a procedure to extract path information that helps high quality transition ATPG. Experimental results show that the proposed method improves SDQL (Statistical Delay Quality Level) by not only accurate calculation of the longest sensitizable paths but also detection of faults through longer paths

Low-capture-power test generation for scan-based at-speed testing

Scan-based at-speed testing is a key technology to guarantee timing-related test quality in the deep submicron era. However, its applicability is being severely challenged since significant yield loss may occur from circuit malfunction due to excessive IR drop caused by high power dissipation when a test response is captured. This paper addresses this critical problem with a novel low-capture-power X-filling method of assigning 0's and 1's to unspecified (X) bits in a test cube obtained during ATPG. This method reduces the circuit switching activity in capture mode and can be easily incorporated into any test generation flow to achieve capture power reduction without any area, timing, or fault coverage impact. Test vectors generated with this practical method greatly improve the applicability of scan-based at-speed testing by reducing the risk of test yield lossIEEE International Conference on Test, 2005, 8 November 2005, Austin, TX, US