Addressing the Non-Magnetic Inductor Need in Medical Electronics

Consider, for just one moment, the ability to monitor human brain activity at its source. Imagine the knowledge that could be gleaned by directly observing the non-stop electric symphony composed and conducted by a 120 billion-piece neuronal orchestra.
 
Fancy gaining a ringside seat to this cerebral concerto, without the need for big, bulky machines, strange-looking skull caps, or long, tangle-prone wires. A tiny, perhaps flexible, electrode would suffice as the entrance fee.
 
To truly witness the magical harmony of the brain’s electric oscillations, that electrode would have to be extremely small—conceivably, 100 nanometers or so (roughly 1,000 times thinner than a human hair).
 
Creating an electrode of that size certainly is technologically possible. Medical electronics have steadily been shrinking over the last two decades as digital health and minimally invasive surgical procedures spawned a worldwide thirst for smaller, more complex computerized devices that improve diagnoses and tracking. The scramble for diagnostic tests, personal protective equipment, ventilators, and other medical supplies associated with the planet’s battle against COVID-19 is expected to increase demand for medical electronics over the next seven years.
 
Medical Product Outsourcing’s September feature, “Mission Complete,” details the various trends and challenges currently shaping the custom medical electronics market. Don Minnick, sales and marketing manager at Gowanda Electronics, was among the experts interviewed for this story. His full input is provided in the following Q&A:
 
Michael Barbella: What factors must be taken into consideration when designing electronic components for medical devices?
Don Minnick: Part performance, size, operating temperature, manufacturability and reliability are key factors when designing components for medical devices. In some applications solvent-resistance or the need for non-magnetic materials can be an additional requirement.
 
Barbella: Please discuss some of the challenges in designing and manufacturing electronic components for medical devices. How has your company overcome these challenges?
Minnick: The need for non-magnetic inductors for applications where magnetic materials must be avoided (as in magnetic resonance imaging) is particularly challenging. As a passive component, the inductor’s purpose is to store energy in a magnetic field when electric current passes through it, thereby protecting the device’s circuitry. Traditional inductors consist of a magnetic core (iron or ferrite) and a wirewound coil. To address the need for a non-magnetic inductor, Gowanda developed a proprietary material which is truly non-magnetic but provides inductance qualities. The company utilizes a magnetoscope to test its material and to confirm the lack of magnetism, thereby giving customers documented evidence to support the non-magnetic distinction, unlike other manufacturers whose claims are unsupported. In fact, Gowanda’s non-magnetic components provide relative permeability of ≤ 1.00003. For design flexibility, they are available in surface mount and through-hole configurations.

Barbella: What are customers demanding or expecting in their electronic components?
Minnick: Customers are demanding high performance inductors to have tight inductance tolerance, as low as ±1 percent, compared to other less stringent applications where that tolerance might be as high as ±20 percent. This tolerance tightening requires Gowanda to pursue innovative approaches to inductor design, often resulting in application-specific solutions.
 
Barbella: How is the trend toward miniaturization of medical devices driving the design of electronic components? Please explain.
Minnick: Miniaturization of devices continues to impact the design of electronic components. There are some practical limits to the size of an inductor due to the electrical performance characteristics required, but novel approaches have enabled development of very small conical inductors which are barely 2.6mm in size versus traditional inductors which can be up to 15mm in size.
 
Barbella: In what ways is the changing regulatory environment impacting electronic component development?
Minnick: The importance of electronic component manufacturers having ISO 13485 certification continues to increase in the medical device marketplace. Understanding the significance of that certification, Gowanda was the first inductor manufacturer to attain ISO 13845, establishing it as a leader in the field. This ISO certification ensures Gowanda’s in-process oversight is at the highest levels for life-critical and implantable component solutions, where both high performance and reliability are essential.
 
Barbella: The industry has grappled with a worldwide electronic components shortage in recent years. What solutions are available to tackle this problem? 
Minnick: Gowanda implemented a vertical integration strategy several years ago to bypass supply chain issues and avoid dependence on (overseas) suppliers. The company now has over 225,000 square feet of design, development and manufacturing space spread out over eight facilities all located in the U.S. Gowanda’s Technology Center focuses on the design, prototype and commercial development of custom solutions, including in-house development of materials and production methods, some involving proprietary equipment. An in-house Environmental Testing Lab gives Gowanda control over the timely testing of its materials and components. Several in-house cleanrooms provide controlled environments when required for specific customers or applications. As a result of this comprehensive vertical integration strategy, the company has been able to address customer needs without interruption.
 
Barbella: Component obsolescence is a challenge in the medtech industry, where the product lifecycle is very long compared to many consumer devices. How can this challenge be overcome?
Minnick: We have a purposeful strategy of “no design obsolescence” so we already have in place the necessary procedures and processes to assure customers that the Gowanda components they’ve designed-in and/or have come to depend on will be available now and in years to come. This puts us in an excellent position to serve the needs of the medtech industry and its extended product life cycles.
 
Barbella: Please discuss any other trends you are noticing in electronic component development (medical devices).
Minnick: Gowanda supplies components to many companies involved in the manufacture of medical devices and equipment that are important in the fight against COVID-19. As the need for such equipment escalated as the virus continued to spread, we were able to quickly ramp up production of those required components thanks to our vertical integration and commitment to our customers. Going forward, as medical device companies innovate and create new products to address COVID-19 and other medical challenges, we will keep in step, as always, by working closely with them and their design teams to assure we design components to meet, if not exceed, their requirements.