Throughout the COVID-19 pandemic, Knowles Precision Devices has stayed focused on our primary goal of helping our customers address their most challenging application needs by providing high-performance components and innovative solutions. While 2021 did offer some unique challenges, overall, it was an exceptional year for our business. This is because even though all the unprecedented circumstances we saw in 2020, we were able to quickly adapt our business, making us really well positioned heading into 2021. As a result, this year was one of our best growth years to date.

Many power electronics today are being designed for use in high-temperature, high-voltage environments, such as inside electric vehicles (EVs). However, size, weight, and power (SWaP) are also key factors driving electronic product development. These conflicting design criteria are an issue for many electrical engineers because space is not available to simply add a cooling system, as this will add weight and increase the product’s overall footprint. Therefore, many of these electronic components are susceptible to “running hot” at the high temperatures and high voltages used in these tiny spaces.

From systems that diagnose, like a magnetic resonance imaging (MRI) machine, to implantable devices that treat patients, like pacemakers and implantable cardioverter-defibrillator (ICDs), highly reliable electronic components are necessary. While the functionality of these devices is quite different, the challenges associated with designing these devices, such as selecting failsafe electronic components designed for lifetime reliability and ensuring supplier partners can meet industry-specific standards, are shared. Let’s look more closely at some of the industry-wide challenges associated with electronic component selection for medical devices as well as some of the application-specific decisions medical device designers need to make to ensure these devices function consistently and reliably for the long term.

When designing a ceramic capacitor, the type of dielectric used will influence the characteristics of the capacitor and define its electrical behavior. At a high level, there are two types of dielectrics made with ceramics – paraelectric and ferroelectric. Dielectrics containing paraelectric (or non-ferroelectric) ceramics are known as Class I dielectrics. These dielectrics show a linear relationship of polarization to voltage and are formulated to have a linear temperature coefficient. Capacitors using a Class I dielectric have high stability across various temperatures, but have low permittivity, which means the capacitor will offer low capacitance.

Achieving high capacitance means going big. But how do you do that while still maximizing board space? At Knowles Precision Devices, we’ve developed a new method for building customizable large capacitor assemblies that capitalize on the vertical space above the circuit board. While stacked capacitor assemblies have been around for many years, these parts do not have very good bump and vibration withstand due to the thin leads used in their construction. These new assemblies from Knowles Precision Devices offer a ruggedized construction capable of withstanding high levels of shock and vibration. This offers a unique combination of capability, durability, high capacitance, and very high voltage in a smaller area, making these capacitors ideal for automotive, military, and aerospace applications.

The millimeter wave (mmWave) part of the electromagnetic spectrum is at the high end of the microwave region, which spans ~300 MHz to 300 GHz, and is usually taken to mean frequencies from ~30 GHz to 300 GHz and wavelengths in the range of 1mm to 1cm (Table 1). This dramatically increases available bandwidth, thus expanding achievable data rates, which makes these frequencies extremely interesting to teams around the world working on fifth generation (5G) communications.

As complex electronic systems become more prevalent in our daily lives, the demand for high-temperature, high-reliability components continues to increase. Standard electronic components have an operating temperature of -55 °C to 125 °C, but the number of applications requiring functionality above 125 °C is growing. Components in these applications, like capacitors, must maintain their functionality and take the heat (literally and figuratively) while powered. To meet the brief, material and design of these high-temperature components must deviate from today’s standard.

At Knowles Precision Devices, we thrive on working with companies who want to take technically challenging ideas and work through the details to figure out how to turn their seemingly impossible ideas into reality. This is because we are not limited to volume production and have extensive experience making specialty and custom parts. We are also familiar with the challenges associated with delivering high-reliability components as we supply many industries and applications that depend on the consistent functionality of custom-shaped parts. For example, we provide numerous space grade components and we are the only manufacturer who has developed planar array ceramic parts for the International Space Station. 

Many critical military operations around the world are increasingly relying on a variety of electronic warfare devices for a range of threat suppression, detection, and neutralization activities. This means that numerous devices operating across the RF spectrum including low-frequency devices in the VHF band and mmWave devices in the Ka band are necessary. As shown in Figure 1, when many electronic warfare devices are in use, a large number of signals are being sent and received and crossing paths. Therefore, it’s easy for any one of these devices to experience issues with interference if proper filtering techniques are not in place.

We are pleased to announce that the Knowles Corporation recently acquired Integrated Microwave Corporation (IMC), a leader in the design and manufacture of custom precision RF microwave filters and multiplexers for the aerospace, defense, and communications industries. With this acquisition, the Knowles Precision Devices Microwave group can now offer a complete range of RF and microwave filtering solutions that support applications from the VHF to the Ka band. In addition to the small, temperature-stable filters our customers have come to know us for, we can now deliver ceramic and cavity filters for lower frequency and/or higher power applications. The full range of the IMC filter technologies we now offer is shown in the graphic below.