Search results

1 – 10 of 55
Article
Publication date: 1 January 1993

J. Barrett, C.O Mathúna and R. Doyle

Rapid feedback on the effect of changes in materials or assembly process parameters on solder joint quality is essential in process optimisation for fine pitch surface…

Abstract

Rapid feedback on the effect of changes in materials or assembly process parameters on solder joint quality is essential in process optimisation for fine pitch surface mount solder assembly. This is particularly the case where the demands of high volume production do not allow lengthy experimentation to be carried out on the production line. The greater precision and care required in analysis of fine pitch solder joints places a further constraint on the speed at which the analysis can be carried out. The techniques of microstructural analysis, solder joint mechanical strength testing and short duration environmental stress testing must be used to meet a rapid turnaround quality and reliability analysis requirement and to maximise the amount of information obtained from each stage of the analysis. Three case studies are detailed which demonstrate the use of these techniques in a high volume production context to provide rapid feedback on joint quality. The case studies have been selected for presentation not only to demonstrate the analysis techniques but also because they address issues which are of current interest due to the increased usage of fine pitch packages in production and the constraints on the use of solvents for cleaning of circuit boards. The studies are:

Details

Soldering & Surface Mount Technology, vol. 5 no. 1
Type: Research Article
ISSN: 0954-0911

Article
Publication date: 1 March 1990

Colin Lea and C. O Mathuna

A large group of SMART Group members visited the Henley premises of Electrovert on 9 May. After the welcome and introduction where Mike Judd emphasised Electrovert's…

Abstract

A large group of SMART Group members visited the Henley premises of Electrovert on 9 May. After the welcome and introduction where Mike Judd emphasised Electrovert's commitment to SMT, a number of papers were presented by the Electrovert team during the morning session.

Details

Soldering & Surface Mount Technology, vol. 2 no. 3
Type: Research Article
ISSN: 0954-0911

Article
Publication date: 1 April 1998

Stephen O’ Reilly, John Flannery, Terence O’ Donnell, Andrew Muddiman, Gerard Healy, Michael Byrne and Sean Cian Ó Mathúna

Multilayer aircore inductors fabricated in a range of interconnection technologies which are MCM compatible are presented and compared. These consist of thick‐film, low…

357

Abstract

Multilayer aircore inductors fabricated in a range of interconnection technologies which are MCM compatible are presented and compared. These consist of thick‐film, low temperature cofired ceramic (LTCC), printed circuit board (PCB) and fine‐line plated copper on ceramic (copper plating). From a comparison of simulated and measured results, it can be concluded that a predictive design capability has been achieved for inductance and self‐resonant frequency (SRF). Modelling of AC resistance and Q requires further investigation.

Details

Microelectronics International, vol. 15 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

Content available
Article
Publication date: 31 July 2009

J. Buckley, B. O'Flynn, J. Barton and S.C. O'Mathuna

The purpose of this paper is to develop a highly miniaturized wireless inertial sensor system based on a novel 3D packaging technique using a flexible printed circuit…

4692

Abstract

Purpose

The purpose of this paper is to develop a highly miniaturized wireless inertial sensor system based on a novel 3D packaging technique using a flexible printed circuit (FPC). The device is very suitable for wearable applications in which small size and lightweight are required such as body area network, medical, sports and entertainment applications.

Design/methodology/approach

Modern wireless inertial measurement units are typically implemented on a rigid 2D printed circuit board (PCB). The design concept presented here is based around the use of a novel planar, six‐faceted, crucifix or cross‐shaped FPC instead of a rigid PCB. A number of specific functional blocks (such as microelectromechanical systems gyroscope and accelerometer sensors, microcontroller (MCU), radio transceiver, antenna, etc.) are first assigned to each of the six faces which are each 1 cm2 in area. The FPC cross is then developed into a 1 cm3, 3D configuration by folding the cross at each of five bend planes. The result is a low‐volume and lightweight, 1 cm3 wireless inertial sensor that can sense and send motion sensed data wirelessly to a base station. The wireless sensor device has been designed for low power operation both at the hardware and software levels. At the base station side, a radio receiver is connected to another MCU unit, which sends received data to a personal computer (PC) and graphical user interface. The industrial, scientific and medical band (2.45 GHz) is used to achieve half duplex communication between the two sides.

Findings

A complete wireless sensor system has been realized in a 3D cube form factor using an FPC. The packaging technique employed during the work is shown to be efficient in fabricating the final cubic system and resulted in a significant saving in the final size and weight of the system. A number of design issues are identified regarding the use of FPC for implementing the 3D structure and the chosen solutions are shown to be successful in dealing with these issues.

Research limitations/implications

Currently, a limitation of the system is the need for an external battery to power the sensor system. A second phase of development would be required to investigate the possibility of the integration of a battery and charging system within the cube structure. In addition, the use of flexible substrate imposes a number of restrictions in terms of the ease of manufacturability of the final system due to the requirement of the required folding step.

Practical implications

The small size and weight of the developed system is found to be extremely useful in different deployments. It would be useful to further explore the system performance in different application scenarios such as wearable motion tracking applications. In terms of manufacturability, component placement needs to be carefully considered, ensuring that there is sufficient distance between the components, bend planes and board edges and this leads to a slightly reduced usable area on the printed circuit.

Originality/value

This paper provides a novel and useful method for realizing a wireless inertial sensor system in a 3D package. The value of the chosen approach is that a significant reduction in the required system volume is achieved. In particular, a 78.5 per cent saving in volume is obtained in decreasing the module size from a 25 to a 15 mm3 size.

Details

Microelectronics International, vol. 26 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 24 April 2007

Brendan O'Flynn, D. Laffey, J. Buckley, J. Barton and S.C. O'Mathuna

This paper aims to describe the simulation, design, development and characterisation of antennas for wireless sensor networks operating in a variety of environments…

2087

Abstract

Purpose

This paper aims to describe the simulation, design, development and characterisation of antennas for wireless sensor networks operating in a variety of environments, including an under water submarine application and more usual “open air” deployments.

Design/methodology/approach

The experimental test methodology, fixtures, conditions and results used to characterize the performance of these antennas (both state of the art commercially available and those developed in‐house) are presented.

Findings

The underwater test results show a near omni‐directional pattern about the three principal axes, thus showing that a spherical field has been achieved for localisation purposes (with a certain loss of resolution).

Originality/value

The paper focuses on the development of a new antenna scheme to enable under water communications between robotic agents.

Details

Microelectronics International, vol. 24 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 1 March 1991

Bob Willis, Glyn Jackson, Colin Lea, C.O Mathuna and Padraig Healy

Electronics exhibitions are the same the world over, very tiring affairs. If your stand is busy, time flies; if not, the strain is more noticeable.

Abstract

Electronics exhibitions are the same the world over, very tiring affairs. If your stand is busy, time flies; if not, the strain is more noticeable.

Details

Soldering & Surface Mount Technology, vol. 3 no. 3
Type: Research Article
ISSN: 0954-0911

Article
Publication date: 1 December 2001

Stephen O’Reilly, Maeve Duffy, Terence O’Donnell, Paul McCloskey and Seán Cian Ó Mathúna

This paper will focus on the work which was carried out under the Brite‐EuRAM funded project, COMPRISE (BE 96‐3371), the objective of which was to develop new materials…

Abstract

This paper will focus on the work which was carried out under the Brite‐EuRAM funded project, COMPRISE (BE 96‐3371), the objective of which was to develop new materials and manufacturing processes to embed passive components (resistors, inductors, capacitors) within printed wiring structures fabricated from laminate materials. For the realisation of integrated resistors, a commercially available planar resistor material is incorporated in different test structures. The technology consists of a copper foil of standard thickness on which a resistive layer is deposited by means of electroless plating. For the realisation of capacitors in multi‐layered PCB structures, significant progress was made in the development and fabrication of very thin laminates. Higher dielectric constants of these laminate materials enable the increase of the capacitance per unit area. For inductors, both aircore (no magnetic material) and magnetic core components have been investigated.

Details

Circuit World, vol. 27 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 1 August 2005

Brendan O'Flynn, S. Bellis, K. Mahmood, M. Morris, G. Duffy, K. Delaney and C. O'Mathuna

To describe the development of a three dimensional programmable transceiver system of modular design for use as a development tool for a variety of wireless sensor node…

Abstract

Purpose

To describe the development of a three dimensional programmable transceiver system of modular design for use as a development tool for a variety of wireless sensor node applications.

Design/methodology/approach

As a stepping‐stone towards the development of wireless nodes, sensor networks programme was put in place to develop a 25 mm cube module, which was modular in construction, programmable and miniaturised in form factor. This was to facilitate the development of wireless sensor networks for a variety of different applications. The nodes are used as a platform for sensing and actuating through various parameters, for use in scalable, reconfigurable distributed autonomous sensing networks in a number of research projects currently underway in the Tyndall Institute, as well as other institutes and in a variety of research programs in the area of wireless sensor networks.

Findings

The modular construction enables the heterogeneous implementation of a variety of technologies required in the arena of wireless sensor networks: Intelligence, numerical processing, memory, sensors, power supply and conditioning, all in a similar form factor. This enables rapid deployment of different sensor network nodes in an application specific fashion.

Research limitations/implications

Characterisation of the transceiver module is ongoing, particularly in the field of the wireless communication platform utilized, and its capabilities.

Practical implications

A rapid prototyping and development cycle of application specific wireless sensor networks has been enabled by the development of this modular system.

Originality/value

This paper provides information about the development work and some potential application areas made available by the implementation of a miniaturised modular wireless sensor node for use in a variety of application scenarios.

Details

Microelectronics International, vol. 22 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 1 January 1991

The popular reflow day was repeated at Henley and commenced with Mike Judd giving an overview of current reflow techniques.

Abstract

The popular reflow day was repeated at Henley and commenced with Mike Judd giving an overview of current reflow techniques.

Details

Soldering & Surface Mount Technology, vol. 3 no. 1
Type: Research Article
ISSN: 0954-0911

Article
Publication date: 1 February 1986

Nihal Sinnadurai, G. Kersuzan, B.S. Sonde, Boguslaw Herod, Brian C. Waterfield, J.B. Knowles and M.A. Stein

I was an invited speaker to the ISHM‐Benelux meeting. As I arrived early, I also sat in on the committee meeting as an observer. Jos B. Peeters was the outgoing president…

Abstract

I was an invited speaker to the ISHM‐Benelux meeting. As I arrived early, I also sat in on the committee meeting as an observer. Jos B. Peeters was the outgoing president and the incoming committee was widened to about 15 members compared with the previous 6. Following the unanimous election of all those nominated, the committee reconvened and elected Mr Kwikkers as the new president of ISHM‐Benelux. He is a professor at the Technische Hogeschole in Delft.

Details

Microelectronics International, vol. 3 no. 2
Type: Research Article
ISSN: 1356-5362

1 – 10 of 55