In power electronics, the DC link refers to the section that connects the input and output sides of the power conversion system (Figure 1). The primary function of the DC link is to store energy during the times when the input power is higher than the output power and release energy when the output power demand exceeds the input power. The DC link should include a capacitor that servers as a supporting filter to act as a buffer, minimize voltage ripples, and smooth and stabilize the power flow between various components such as rectifiers, inverters, and other converters in the power system.

Large voltage spikes are common in power circuits, particularly during switching—a core action for device functionality. As a result, voltage suppression is a fundamental system requirement to protect circuits.

Enter: snubber capacitors

Q factor, or quality factor, is an electrical term used to describe the ratio of energy stored to energy dissipated in a capacitor at a certain frequency (you can learn more about the different components of Q factor and ways to define it here). In other words, Q factor tells us how good a capacitor is at its job at a certain frequency. A high Q value indicates low energy loss during operation, making these capacitors a good fit for applications requiring low power dissipation and high stability.  

A medical device is considered “implantable” if it’s partly or totally introduced into the human body via surgery or another medical intervention, and it’s intended to stay there for a long period of time. According to the American Medical Association (AMA), approximately 10 percent of Americans will receive an implantable device during their lifetimes. To serve consistent, often life-sustaining functions, implantables require high-reliability components that guarantee long-term performance.

As you likely know, capacitors are used in electronic circuits to provide local energy storage and stabilize power supply voltage. Decoupling capacitors are a specific type of capacitor used to isolate or decouple two circuits. In other words, these capacitors decouple AC signals from DC signals or vice versa. Decoupling capacitors act as a buffer, supplying clean and stable power to components, which minimizes the risks of malfunctions, noise coupling, or signal integrity issues.

As electric vehicle (EV) manufacturers work to make batteries more affordable and easier to produce in mass quantities, we’re seeing changes in battery chemistry. For example, the industry is shifting from traditional lithium ion batteries with cobalt to lithium iron phosphate (LFP) batteries. Rare-earth metals like cobalt are in short supply, and materials like LFP are a more plentiful, sustainable, and efficient alternative.

Radio frequency (RF) and microwave applications involve transmitting and receiving electromagnetic signals at high frequencies. While these terms are often used interchangeably, RF means AC signals at 3 kHz to 300 GHz. For microwave, it’s more like 300 MHz to 300 GHz. Capacitors play a central role in these applications because they are concerned with capacitance, naturally, and impedance (i.e., resistance), which vary with frequency. Functionally, these passive electronic components store energy in an electric field. 

To understand what an electromagnetic interference (EMI) filter is, and what it does, we need to first know what EMI is and why it needs to be filtered. EMI refers to undesirable electromagnetic emissions or disturbances generated either by electronic devices or natural sources in the environment that can interfere with the proper functioning of other nearby devices or systems. EMI noise can propagate through power supply lines and radiate into the environment, potentially causing disruptions or malfunctions in other electronic systems. For many devices, this could cause big issues, which is why many government organizations have developed regulatory standards for electromagnetic compatibility (EMC), or when two pieces of electronic equipment can function in the same environment without adversely impacting one another. 

Welcome to the Capacitor Fundamentals Series, where we teach you about the ins and outs of chips capacitors – their properties, product classifications, test standards, and use cases – in order to help you make informed decisions about the right capacitors for your specific applications. After describing standard industry test testing in our previous article, let’s discuss high reliability testing for capacitors.

One of the primary goals in electric vehicles (EVs) is to increase the efficiency of its power conversion devices. The more efficiently power is converted, the further distance the EV can travel on one charge. For example, by reducing losses in a DC-to-DC (or DC/DC) converter, the converter (and overall vehicle) benefits from improved energy efficiency, a more streamlined design, and diminished heating from components.