The explosion of the Internet onto the worldwide scene, combined with the growth of corporate Intranets, telecommuting, and the small-office-home-office marketplace, has fueled an unprecedented demand for high-speed connectivity. To boost efficiency, many ISDN makers are converting their designs to 100% surface mount technology (SMT) components and processes.
Pulse engineers redesigned the new SMT transformer around an "open frame" construction that reduces the overall weight at the heart of the component. The new component's winding bobbins are formed from high-temperature plastic and internal solder connections using high-temp solder to resist any potential for component degradation from the 220 to 230C temperatures in today's SMT reflow ovens.
A key issue raised during discussions with OEM manufacturers was the need for a highly consistent level of co-planarity between all of the transformer leads to ensure required SMT production yields. Pulse engineers redesigned the production process to simultaneously form all of the leads in a single step, thus eliminating problems of lead 'lift' and improving solder joint integrity.
The use of SMT transformers can significantly improve the cost and quality of ISDN systems by allowing greater levels of automation, reduction of manual operations, more efficient use of PCB real estate, and improved consistency of system yields. Empirical testing has shown that SMT transformers are just as durable and reliable as through-hole components. Plus as a result of im-proved production efficiency and reduced handling costs, the final "applied costs" of using the new SMT components is significantly less.
To reach the author or a Pulse representative, e-mail mikemcwilliams@pulseeng.com; or call (619) 674-8100.