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Electronic Components (electronic + component)

Distribution by Scientific Domains
Polymers and Materials Science57%

Selected Abstracts

Ionic Liquids: Electropolymerization of a Bifunctional Ionic Liquid Monomer Yields an Electroactive Liquid-Crystalline Polymer (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 13 2010
Mater.
M. A. Firestone et al. present a polymer that incorporates an electronic component with an ionic liquid and produces a mixed ionic and electronic conductor on page 2063. Electropolymerization of a bifunctional imidazolium-based ionic liquid monomer incorporating both vinyl and thiophene groups yields a liquid-crystalline polymer that adopts an interconnected network structure formed by two orthogonally oriented lamellar sheets. The structural ordering leads to enhanced electrical conductivity. [source]

Foldable Printed Circuit Boards on Paper Substrates

ADVANCED FUNCTIONAL MATERIALS, Issue 1 2010
Adam C. Siegel
Abstract This paper describes several low-cost methods for fabricating flexible electronic circuits on paper. The circuits comprise i) metallic wires (e.g., tin or zinc) that are deposited on the substrate by evaporation, sputtering, or airbrushing, and ii) discrete surface-mountable electronic components that are fastened with conductive adhesive directly to the wires. These electronic circuits,like conventional printed circuit boards,can be produced with electronic components that connect on both sides of the substrate. Unlike printed circuit boards made from fiberglass, ceramics, or polyimides, however, paper can be folded and creased (repeatedly), shaped to form three-dimensional structures, trimmed using scissors, used to wick fluids (e.g., for microfluidic applications) and disposed of by incineration. Paper-based electronic circuits are thin and lightweight; they should be useful for applications in consumer electronics and packaging, for disposable systems for uses in the military and homeland security, for applications in medical sensing or low-cost portable diagnostics, for paper-based microelectromechanical systems, and for applications involving textiles. [source]

Zero Shrinkage of LTCC by Self-Constrained Sintering

INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 5 2005
Torsten Rabe
Low shrinkage in x and y direction and low tolerances of shrinkage are an indispensable precondition for high-density component configuration. Therefore, zero shrinkage sintering technologies as pressure-assisted sintering and sacrificial tapes have been introduced in the low-temperature co-fired ceramics (LTCC) production by different manufacturers. Disadvantages of these methods are high costs of sintering equipment and an additional process step to remove the sacrificial tapes. In this article, newly developed self-constrained sintering methods are presented. The new technology, HeraLock®, delivers LTCC modules with a sintering shrinkage in x and y direction of less than 0.2% and with a shrinkage tolerance of ±0.02% without sacrificial layers and external pressure. Each tape is self-constrained by integration of a layer showing no shrinkage in the sintering temperature range of the LTCC. Large area metallization, integration of channels, cavities and passive electronic components are possible without waviness and camber. Self-constrained laminates are an alternative way to produce zero shrinkage LTCC. They consist of tapes sintering at different temperature intervals. Precondition for a successful production of a self-constrained LTCC laminate is the development of well-adapted material and tapes, respectively. This task is very challenging, because sintering range, high-temperature reactivity and thermal expansion coefficient have to be matched and each tape has to fulfill specific functions in the final component, which requires the tailoring of many properties as permittivity, dielectric loss, mechanical strength, and roughness. A self-constrained laminate is introduced in this article. It consists of inner tapes sintering at especially low-temperature range between 650°C and 720°C and outer tapes with an as-fired surface suitable for thin-film processes. [source]

EMC internal patch antenna integrated with a U-shaped shielding metal case for mobile device application

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2006
Chih-Ming Su
Abstract A novel integration design of a shorted patch antenna and a U-shaped shielding metal case for application in a mobile communication device is presented. The shorted patch antenna is mounted within the dented portion of the U-shaped shielding metal case, which can provide a coupling-free space for accommodating electronic components such as the RF modules/circuitry and battery in the mobile device. Thus, in this case, the shorted patch antenna can operate as an internal antenna having an electromagnetic compatibility (EMC) property with nearby electronic components. In addition, with the proposed integration design, the shorted patch antenna is isolated from the two side edges of the system ground plane of the mobile device. Hence, it can be expected that the effects of the user's hand on the performances of the antenna will be suppressed. The proposed integration design applied to a smart phone for Universal Mobile Telecommunications System (UMTS, 1920,2170 MHz) operation is studied. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1157,1161, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21552 [source]

Unexpected ICD Pulse Generator Failure Due to Electronic Circuit Damage Caused by Electrical Overstress

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 7 2001
ROBERT G. HAUSER
Hauser, R., et al.: Unexpected ICD Pulse Generator Failure Due to Electronic Circuit Damage Caused by Electrical Overstress. Because it is a lifesaving device, the unexpected failure of an ICD can be catastrophic. We report ICD electronic circuit failure due to electrical overstress damage (EOS) to the high voltage hybrid circuit and other electronic components in a series of ICD pulse generator models. Data were obtained from the Multicenter Registry of Pacemaker and ICD Pacemaker and Lead Failures, and from the manufacturers' adverse event reports, that were in the FDA's Manufacturer and User Facility Device Experience (MAUDE) database. Of 16 nonbattery Guidant/CPI ICD pulse generator failures reported to the registry, 6 (38%) have been confirmed by the manufacturer to be EOS related, and Guidant/CPI has reported 273 such failures to the FDA as of 12/29/00. The signs of failure included loss of telemetry and inability to deliver therapy, and some patients have experienced serious adverse events. Hybrid circuit damage may have occurred during capacitor charging or reform, and the majority appears to have happened during normal ICD function. While the incidence of this problem is unknown, a management strategy should be adopted that includes routine follow-up every 3 months and device evaluation after a shock or exposure to external defibrillation or electrosurgical devices. This study suggests that additional data are needed to determine the incidence of this problem, and that our present methods for monitoring the performance of ICDs following market release are inadequate. [source]