Circuit World: Volume 20 Issue 2

PWB Surface Finishes for COB

D. Landis, J. Notman

When implementing chip‐on‐board (COB), the surface finish on the printed wiring board needs to be chosen with several key considerations in mind. The choice of bonding technology…

Wire‐bonding on Printed Circuit Boards

J. Falk, J. Hauke, G. Kyska

Although wire‐bonding is an established and well‐known technique for micro‐joining on leadframes, direct die‐attach without housing on printed circuit boards has some new…

Electromagnetic Interference in Portable Electronic Products: Emerging Challenges and Opportunities

P. Nyholm, S. Rao, H. Duffy

This paper reviews technologies used for the prevention of electromagnetic interference in current portable electronic products. It studies the need for future advanced products…

No‐clean Flux Appraisal — The Total Process Approach

B.J. Mason

No‐clean flux printed board appraisal tests were conducted with all materials used in the production process. Metallic growths during environmental testing revealed that there was…

Manufacturing Cost Analysis of Surface Mount PCB Designs

M. Alexander, K. Srihari, C.R. Emerson

A product's design influences its manufacturing process and the associated costs. Consequently, design engineers need to review their designs from a manufacturing perspective…

Ionograph Sensitivity to Chemical Residues from ‘No Clean’ Soldering Fluxes: Comparison of Solvent Extract Conductivity and Surface Conductivity

K.M. Adams, J.E. Anderson, Y.B. Graves

This study examines solvent extract conductivity (SEC) testing, e.g., Ionograph or Omega Meter testing, which measures ionic cleanliness of printed wiring boards (PWBs). SEC has…

Productronica '93

‘Quality rather than quantity’ aptly summed up the opinion expressed by exhibitors at the Productronica '93 exhibition in Munich from 9–13 November. The effects of the recession…

PCIF News

The number of printed circuit board (PCB) manufacturers in the UK fell by 60% over the period 1990 to July 1993, according to a new report ‘UK PCB industry 1990–1993’ recently…

International Institute News

Plans to hold this year's CEMEX show at Birmingham have been endorsed by CEMA members at the recent Annual General Meeting. CEMEX '94 will be held in the Pavilion Hall at the…

Industry News

Morton International Inc. have purchased Hoechst AG's printed circuit materials business including their Ozatec dry film and liquid primary imaging photoresists, Ozatec liquid…

New Products

Du Pont Electronic Materials have introduced a new liquid, photo‐imageable solder mask, which combines the advantages of environmentally acceptable aqueous processing with high…