Low-noise amplifiers (LNAs) in radio frequency (RF) receivers are designed to amplify low-amplitude signals (i.e., less than -100 dBm) from an antenna without decreasing their signal-to-noise ratio (SNR). In radar applications, a strong SNR increases the likelihood of detecting a target, so LNAs play an important functional role (Figure 1). Effective targeting requires both high resolution and high accuracy. A strong SNR translates to high accuracy.  

In an ideal world, capacitors could be designed in a way where they would exhibit no resistance. However, this is physically impossible to achieve as there will always be some type of internal resistance in a capacitor that appears in series with the capacitance of the device. Known as equivalent series resistance (ESR), the level of this resistance will vary across capacitors depending on a variety of factors including the dielectric materials used, frequency of the application, leakage, and quality and reliability of the capacitor. The two graphs in Figure 1 show an example of how ESR can change as frequency increases across various capacitances on two different classes of ceramic dielectrics.

Defibrillators are designed to deliver electric current to the heart, in the form of a controlled shock to the myocardium, to treat arrhythmias and restore the heartbeat back to normal. Capacitors play an important role in the function of these life-saving devices. Here, we’ll cover the basic components of a defibrillator circuit and explore the role of capacitor selection in defibrillator system design. 

Electrical arcing can cause any number of issues in a circuit that lead to unreliable operation. Without effective snubbing, arcing is associated with early failures in relays, switch contacts and solid-state components (e.g., SCRs and TRIACs). 

When it comes to aerospace and defense applications, every single component plays a role in the success and longevity of the system. Capacitors are vital in flight control systems, radar systems, signal intelligence equipment and more. They support functions across guidance and control systems, electronic warfare (EW) and power supply units. To best support these development projects, Knowles sought MIL-PRF-55681 qualification for ten capacitor styles we manufacture and test in the United States. With this qualification, you can be assured that you’re using robust and dependable ceramic capacitors in your mission-critical systems. 

As consumers demand rapid, and accurate, delivery of online orders, yet labor shortages continue to prevail, distributors need to increase efficiency and productivity, reduce errors, and improve inventory management in their warehouses. To do this, distributors must modernize warehouse logistics by creating smart warehouses that incorporate technologies such as automated guided vehicles (AGVs), automated mobile robotics (AMRs), IIoT sensors, drones, and/or robotic arms. Using these technologies, distributors can streamline operations by automating and accelerating tasks such as order picking, inventory replenishment, automated storage and retrieval, and goods transportation.

The types of threats facing radar systems are continuing to diversify. To adapt, the industry is evolving toward fully digital arrays that can support a variety of mission profiles. As these systems grow more and more complex, component-level decisions have an increasingly significant impact on overall performance.   

As power conversion systems evolve to leverage higher voltages and wide bandgap semiconductors like silicon carbide (SiC) and gallium nitride (GaN), system designers face new challenges in managing the electromagnetic interference (EMI) frequency landscape. Here’s how EMI filters play an important role in ensuring safe operation at higher voltages. 

Monolithic microwave integrated circuit (MMIC) amplifiers are widely used in defense radar systems. The industry recognizes them as a compact, high-performance option that’s reliable and easy to integrate. Whether they serve a receive (e.g., low noise amplifier (LNA)) or transmit (e.g., power amplifier (PA)) function, MMIC amplifiers rely on bypass capacitors to perform their core function to amplify microwave signals. 

Radio frequency (RF) and microwave applications involve the transmission and receipt of high-frequency electromagnetic signals. RF refers toalternating current (AC) signals at 3 kHz to 300 GHz, and microwave refers to a higher range, closer to 300 MHz to 300 GHz. Capacitance, and by extension impedance, varies with frequency, so capacitors play a variety of critical roles in these RF and microwave circuits. With many options for configuration, they function in energy storage and voltage regulation, DC blocking, impedance matching, filtering and more.