Advances in electronics technology are quickly bridging the gap from consumer products to medical devices. Medical equipment mirrors consumer goods in that it is becoming more compact and wireless. But as these highly complex devices become more common in hospitals, clinics, and home care settings, it is becoming more important to ensure the electromagnetic compatibility and safety of these devices when used together.

Inadequately protected devices and components may be susceptible to electromagnetic interference (EMI), which causes malfunctions and even failures of sensitive devices. International electromagnetic compatibility (EMC) standards mandate that manufacturers certify the electromagnetic compatibility of their medical devices based on limits established by the International Electrotechnical Commission. The Center for Devices and Radiological Health, a division of the FDA, along with the Association for the Advancement of Medical Instrumentation, have also developed guidance standards for medical device manufacturers seeking pre-market approval.

Larger electronic equipment may us Faraday cages, or metal enclosures, around EMI-emitting devices to wall them off from other components and machines. However, today's complex, miniaturized electronics need smaller and lightweight shielding.

Some manufacturers wrap metallic film or foil around emitting components. This protects other components in the device as well as nearby equipment. However, most equipment is vulnerable to interference leaking through enclosure openings for cables and switches, as well as seams in enclosures. In these areas, conductive gaskets and seals can control exposure.

Electrically conductive tapes can also act as seals and gaskets. Such tapes are comprised of homogeneous, conductive adhesives coated onto a number of specialized metallized fabric or foil carriers that ensure current continuity between components. They are inherently conformable and can be provided in either roll form or fabricated into precise, die-cut components.

Custom capabilites

In recent years, advancements in conductive tapes have let companies tailor the physical properties of adhesives to provide stable conductivity over a wide range of environmental conditions, including humidity and fluctuating temperatures. And some conductive adhesive bonds can handle harsh impacts, such as those encountered if a device is dropped.

Conductive tapes can be formulated from silicone, acrylic or rubber polymers for maximum flexibility and compatibility with most metal or film substrates. Today, engineers have more material choices in conductive films than ever, including metal-coated polyesters, metal-plated mesh fiber, and carbon mesh. These materials are meeting today's medical electronics EMI challenges.