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. 

DC link capacitors are commonly used in power converters as an intermediary buffer between an input source to an output load that have different instantaneous power, voltages, and frequencies. In electric vehicle (EV) applications, DC link capacitors help offset the effects of inductance in inverters, motor controllers, and battery systems. They also serve as filters that protect EV subsystems from voltage spikes, surges, and electromagnetic interference (EMI).

Ongoing innovation in solar power electronics and rising interest in photovoltaic (PV) installations underscores the importance of robust and efficient electronic components. Capacitors play a key role in power conversion systems as they function to smooth and regulate power flow, protect against voltage surges and filter unwanted signals. 

The electrical power systems in most modern technologies, like electric vehicles (EVs), are complex. In EVs specifically, power systems are responsible for performing many tasks such as converting AC to DC and DC to AC as well as managing changing power levels in DC/DC conversion. When performing these tasks, manipulating AC voltages and removing noise from DC voltage requires passive components such as capacitors, to perform many “jobs” inside the power system. But no single capacitor type can perform all these jobs since each one has different requirements for voltage, size, temperature, and reliability. Therefore, a variety of capacitor technologies, such as ceramic, film, and aluminum, are required to meet all these needs.

We recently released new supercapacitor modules that provide a significant jump in voltage rating over typical radial-mount supercapacitors, up to 9.0 WVDC.

To help PCBs and other physically connected components survive vibration, board bending, thermal mismatching, and stress during thermal cycling, Knowles Precision Devices has launched a range of leaded standoff components, Metal Frame J-Lead Terminal MLCCs, that are qualified to AEC-Q200. AEC-Q200 is the global standard for stress resistance in passive electronic components in automotive applications. 

Given that snubber capacitors address the negative impacts of switching, it’s no surprise that they’re most commonly found in switching power supplies. These systems face major challenges from switching, including: 

• Switching transients 
• Parasitic elements 
• High-frequency noise 

Capacitors serve many crucial functions in power electronic circuits. Their ability to store electric charge makes them essential components for regulating and smoothing power flow. 

Many of these capacitors are standard fare, but a few play highly specialized, functional roles. To meet application-specific demands, these capacitors must be selected carefully based on function, size, and interoperability. 

As a fundamental component of circuit design, equivalent series resistance (ESR) is the measurement of all the non-ideal electrical resistances in series with a capacitor. When current flows through a multilayer ceramic capacitor (MLCC) due to application of alternating voltage, heat is generated in the MLCC due to the losses, specifically ESR. As a result, this self-heating can cause various performance and reliability issues in the circuits of today’s more complex and smaller electronic systems.