Testability enhancement of a basic set of CMOS cells

Testing should be evaluated as the ability of the test patterns to cover realistic faults, and high quality IC products demand high quality testing. We use a test strategy based on physical design for testability (to discover both open and short faults, which are difficult or even impossible to detect). Consequentially, layout level design for testability (LLDFT) rules have been developed, which prevent the faults, or at least reduce the chance of their appearing. The main purpose of this work is to apply a practical set of LLDFT rules to the library cells designed by the Centre Nacional de Microelectrònica (CNM) and obtain a highly testable cell library. The main results of the application of the LLDFT rules (area overheads and performance degradation) are summarized and the results are significant since IC design is highly repetitive; a small effort to improve cell layout can bring about great improvement in design

Supply current monitoring in cmos circuits for reliability prediction and test.

The monitoring of supply current in CMOS VLSI devices has been suggested as a tool for both detecting reliability hazards and increasing the effectiveness of standard functional testing. This paper reviews these techniques and describes a method used at Lancaster for evaluating the IDDQ test

Does septal-lateral annular cinching work for chronic ischemic mitral regurgitation?

AbstractObjectivesRing annuloplasty, the current treatment of choice for chronic ischemic mitral regurgitation, abolishes dynamic annular motion and immobilizes the posterior leaflet. In a model of chronic ischemic mitral regurgitation, we tested septal-lateral annular cinching aimed at maintaining normal annular and leaflet dynamics.MethodsTwenty-five sheep had radiopaque markers placed on the mitral annulus and anterior and posterior mitral leaflets. A transannular suture was anchored to the midseptal mitral annulus and externalized through the midlateral mitral annulus. After 7 days, biplane cinefluoroscopy provided 3-dimensional marker data (baseline) prior to creating inferior myocardial infarction by snare occlusion of obtuse marginal branches. After 7 weeks, the 9 animals that developed chronic ischemic mitral regurgitation were restudied before and after septal-lateral annular cinching. Anterior and posterior mitral leaflet angular excursion and annular septal-lateral and commissure–commissure dimensions and percent shortening were computed.ResultsSeptal-lateral annular cinching reduced septal-lateral dimension (baseline: 3.0 ± 0.2; chronic ischemic mitral regurgitation: 3.5 ± 0.4 [P < .05 vs baseline by repeated measures analysis of variance and Dunnett's test]; septal-lateral annular cinching: 2.4 ± 0.3 cm; maximum dimension) and eliminated chronic ischemic mitral regurgitation (baseline: 0.6 ± 0.5; chronic ischemic mitral regurgitation: 2.3 ± 1.0 [P < .05 vs baseline by repeated measures analysis of variance and Dunnett's test]; septal-lateral annular cinching: 0.6 ± 0.6; mitral regurgitation grade [0 to 4+]) but did not alter dynamic annular shortening (baseline: 7 ± 3; chronic ischemic mitral regurgitation: 10 ± 5; septal-lateral annular cinching: 6 ± 2, percent septal-lateral shortening) or posterior mitral leaflet excursion (baseline: 46° ± 8°; chronic ischemic mitral regurgitation: 41° ± 13°; septal-lateral annular cinching: 46° ± 8°).ConclusionsIn this model, septal-lateral annular cinching decreased chronic ischemic mitral regurgitation, reduced annular septal-lateral diameter (but not commissure–commissure diameter), and maintained normal annular and leaflet dynamics. These findings provide additional insight into the treatment of chronic ischemic mitral regurgitation