As demand for high-efficiency and high-power-density inverters continues to grow, the so-called “flying” capacitor multilevel inverter is emerging as a strong choice for many power electronics systems. Since these capacitors can “float” to different electric potentials depending on the connected semiconductor switching structure and state, they help balance out voltage level differences due to manufacturing tolerances, temperature variations, and other factors. These capacitors are also helpful in balancing voltage across the structure by temporarily storing and releasing energy as needed, increasing power density and quality, and optimizing the use of existing voltage availability.
When constructing multilayer ceramic capacitors (MLCCs), there are two classes of dielectrics electrical engineers typically select from depending on the application – Class 1, which consists of non-ferroelectric materials such as C0G/NP0, and Class 2, which are ferroelectric materials such as X5R and X7R. One key difference between these materials comes in the form of capacitance stability as voltage and temperature increase. With Class 1 dielectrics, capacitance will remain stable when DC voltage is applied and operational temperature increases. On the other hand, Class 2 dielectrics, which have a higher dielectric constant (K), are less stable with regards to temperature, voltage, frequency, and time.
Topics: Capacitor
Capacitor Fundamentals: Part 3 – Factors Affecting Capacitance
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 common applications for capacitors in our previous article, let’s consider the factors and limitations that affect capacitance.
Topics: Capacitor
Capacitor Fundamentals: Part 2 – How are Capacitors Used?
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 common use cases – in order to help you make informed decisions about the right capacitors for your specific applications. After discussing capacitance and how capacitors work in our previous article, let’s talk about how capacitors are most frequently used in electronic circuits.
Topics: Capacitor
Welcome to the Capacitor Fundamentals Series, where we teach you about the ins and outs of chips capacitors – their nature and properties, dielectric behavior, product classifications, test and quality standards, and common use cases – in order to help you make informed decisions about the right capacitors for your specific applications. Part 1 discusses the key principles of capacitance and how a basic capacitor works.
Topics: Capacitor
The generation of RF energy is critical for a wide range of technologies including magnetic resonance imaging (MRI), semiconductor manufacturing, industrial lasers, and wireless charging systems that require high-frequency current and minimal instances of power loss. For example, with an industrial laser, the RF plasma excitation, which is when electrons are broken off an atomic bond and plasma forms, requires RF sources ranging from 1kHz to 40.68MHz depending on the energy required, and a CO2 laser RF power supply that contains a standard source at 13.56MHz, 81MHz, or 125MHz.
Topics: Capacitor, RF and Microwave
Selecting MLCCs that Meet the High-Reliability Requirements of Medical Implantable Devices
Designing medical implantable devices for high reliability is crucial for a variety of reasons. First, given the life-critical functions performed by many medial implantable devices, and the invasive procedure required to implant medical equipment properly in the human body, it is imperative that all medical devices are designed to function reliably throughout their entire lifetime. Furthermore, since patient safety is paramount, any precautions to reduce the possibility of potentially life-threatening malfunctions, recalls, and replacement surgeries are necessary. And, beyond preventing patient safety issues, there may also be severe economic and legal implications for device manufacturers if an implantable device fails.
Topics: Capacitor, Medical, High Reliability
New App Note: Everything You Need to Know About Wire Bonding
Today, one of the most cost-effective and flexible electrical interconnection techniques available is wire bonding. With this technique, thin wire and a combination of heat, pressure, and/or ultrasonic energy are used to create a connection between an integrated circuit or other semiconductor devices and device packaging.
Topics: Capacitor
Trimmer capacitors are variable components used to calibrate RF circuits during manufacturing or servicing. These components allow for variable tuning--think oscillator frequency values or rise and fall times. Should values drift over the life of the device, trimmer capacitors can be recalibrated as needed. For sensitive applications like magnetic resonance imaging (MRI), these components help to optimize performance where any instability in time or temperature could impact the image output.
Meeting the Unique Design Requirements for Leadless Pacemaker Electrical Components
Today, millions of people around the world rely on pacemakers to help regulate their heart’s rhythm. A traditional pacemaker usually consists of a pulse generator that is about the size of a tea bag and implanted under the skin near the collarbone, and a wire, or lead, that runs through a blood vessel to the heart. The end of the lead has an electrode on it that touches the heart wall to deliver electrical impulses. However, in the last decade, innovations in pacemaker technology have led to the introduction of a new style of pacemaker, known as the leadless pacemaker, that is about 1/10th the size of a traditional pacemaker, or about the size of a vitamin (Figure 1).
Topics: Capacitor, Medical, High Reliability