Learn More
This paper explains a mechanism of commonmode generation on a printed circuit board with a narrow ground pattern. A transmission line has its value of degree of unbalance. At a connection point of two transmission lines having different degrees of unbalance, common mode voltage is generated proportional to the difference, and it drives common mode current.(More)
BACKGROUND Although the onset mechanism of an olecranon stress fracture (OSF) due to a throwing disorder is believed to involve valgus extension overload, olecranon posteromedial impingement, or triceps traction force, this issue is still debated in the literature. PURPOSE To establish a classification system for the different types of OSFs to improve(More)
Placing a guard trace next to a signal line is the conventional technique for reducing the common-mode radiation from a printed circuit board. In this paper, the suppression of common-mode radiation from printed circuit boards having guard traces is estimated and evaluated using the imbalance difference model, which was proposed by the authors. To reduce(More)
A guard trace placed near a signal line reduces commonmode radiation from a printed circuit board. The reduction effect is evaluated by the imbalance difference model, which was proposed by the authors, when the guard trace has exactly the same potential as the return plane. However, depending on interval of ground connection of the guard trace, the(More)
環境電磁工学の技術課題については,1970年代より 本学会通信ソサイエティ環境電磁工学研究専門委員会 が中心になって情報の交換にあたっている.この問題 は,人間が社会的規模で電気を,特に通信に使い始め たときに,すぐに発生した.以来およそ 100年.周波 数は 100 GHz に,通信距離は火星まで数百万 kmに 及び,地球上で交わされる情報量はすぐには想像もつ かないほど多量であり,個人が日常的に行う通信の情 報速度も 100 Mbit/s が珍しくない.この間に環境電 磁工学の課題は,単に通信にかかわるだけでなく,高 速ディジタル電子装置の放射雑音電磁界,電磁界の生 体に及ぼす影響から電磁現象そのものの解明,放電現 象の科学など,より深い基礎知識の探求と,新たに起(More)
Some recent results from research conducted in the EMC group at Okayama Universiry are reviewed A scheme for power-bus modeling with an analytical method is introduced. A linear macro-model for ICdLSIs. called the LECCS model, has been developed for EM and EMS simulation. This model has a very simple structure and is suficiently accurate. Combining the(More)
We propose a novel technique of matching at both ends of the guard trace to suppress resonance. This approach is derived from the viewpoint that the guard trace acts as a transmission line. We examined that matched termination suppresses guard-trace resonance through simulating a circuit and measuring radiation. We found from these results that the proposed(More)
A LECCS-I/O model of a multi-bit drive IC was devised for reducing electromagnetic interference. An equivalent power circuit model of the IC (74LVC04) was derived from measured power impedances by measuring four test boards. Each board consisted of a single layer, a powerimpedance measurement port, and two output ports from the six IC drivers. The power(More)
Power bus noise problem has become a major concern for both EMC engineers and board designers. A fast algorithm, based on the cavitymode model, was employed for analyzing resonance characteristics of multilayer power bus stacks interconnected by vias. The via is modeled as an inductance and its value is given by a simple expression. Good agreement between(More)
Authors have introduced a quasidi erential signaling system, which is the method to realize low EMI (electromagnetic interference) transmission by matching the degree of imbalance of a line, a driver and a load. In this paper, authors present the measurement result of a common-mode current flowing on a transmission line, which has a narrow return trace. As(More)