Evaluation of very low bending radius of flexible circuits beyond the standard design rules
The Flexible Printed Circuits (FPC) used in high-end applications have some specific characteristics. It has a more complex build-up and must be compatible with repair processes. Moreover, they are used in harsh environment and long mission profile. Current FPC design are based on industrial standards, which propose design rules, such as minimum bending radius calculated from the maximum accepted copper elongation. This work is part of a large study focused on the development of a new generation of digital board solutions for electronic interconnection. In this paper, a finite element simulation study will be applied to FPC bending analysis beyond industrial standard limits. As a conclusion, we propose to consider the maximum copper strain and the bending shape for the minimum bending radius definition.
Flexible Durability of Ultra-Thin FPCB
LS Mtron, 555 Hogye-dong, Anyang-si, Kyounggi-Do, Korea(2014년 11월 11일 접수: 2014년 12월 24일 수정: 2014년 12월 26일 게재확정 )초록: 본 연구에서는 스퍼터링 공정으로 제작된 FCCL(flexible copper clad laminate)을 이용하여 초박형 FPCB를 개발하였다. 또한 구리 박막과 폴리이미드 기판의 접착력을 향상시키기 위한 NiMoNb 접착층을 적용하였다. 개발된 초박형FPCB의 기계적 내구성과 유연성은 인장, 비틀림 및 굽힘 피로 수명시험을 이용하여 검증하였다. 인장 시험 결과 초박형FPCB는 약 7% 까지 인장이 가능하였으며, 비틀림 각도 120
Representation of systems disturbed by wide band noise
In this paper, a method of handling and working with wide band noise is developed. We represent wide band noise as a distributed delay of white noise and use it to reduce a nonlinear system disturbed by wide band noise to a nonlinear system disturbed by white noise. An application of this reduction to a nonlinear filtering problem under a wide band noise disturbance is discussed.