In addition to the International Telecommunications Union (discussed in part 1 of this FAQ series), there are several organizations that define and regulate acceptable levels of conducted and radiated emissions from electronic devices. These various agencies have developed numerous standards generally based on the operational environment of the specific device. Effectively managing EMI is a […]
EMI, EMC, EMS, and the ITU
Controlling electromagnetic interference (EMI), also referred to as radio frequency interference (RFI), and minimizing electromagnetic susceptibility (EMS) are two important aspects of maintaining electromagnetic compatibility (EMC). Ensuring electromagnetic compatibility at a specified level and under specific operating conditions is a common demand in the design of almost all electronic systems. Common terms used when discussing […]
Supercapacitor specifications and lifetimes – Virtual Roundtable (part 2 of 2)
Moderated by Jeff Shepard EE World has organized this “virtual roundtable” bringing together three experts in supercapacitor technology to share with you their experience and practical insights into these important devices. Joining us for this virtual roundtable are: Chad Hall (CH), Co-Founder / Sr. Vice President Sales & Operations, with Ioxus; Eric DeRose (ED), Global […]
Supercapacitor ESR and optimal performance – Virtual Roundtable (part 1 of 2)
Moderated by Jeff Shepard EE World has organized this “virtual roundtable” bringing together three experts in supercapacitor technology to share with you their experience and practical insights into these important devices. Joining us for this virtual roundtable are: Chad Hall (CH), Co-Founder / Sr. Vice President Sales & Operations, with Ioxus; Eric DeRose (ED), Global […]
Sound design considerations for Class D amps
The first two FAQs in this series, “Class D Amplifiers for High-Efficiency Switched-Mode Sound” and “Class D Audio – Why Now?” focused on basic Class D amplifier topologies, modulation techniques, general component and technology advancements that have made Class D amplifiers an increasingly viable option, and the evolving tradeoffs between silicon and GaN power devices. […]
Class D audio – Why now?
Class D amplifiers were first proposed in the 1950s. Why have they only recently been gaining more widespread popularity? The answer involves several factors: There were no switching transistors that met the performance demands of Class D amplifiers until the 1980s. And it was not until the mid-1990s that Class D integrated circuits became available. […]
Class D amplifiers for high-efficiency switched-mode sound
Sound is an analog or linear phenomenon. Traditional audio amplifiers such as Class A and Class AB operate the amplifying transistors in the linear mode. Class A and AB amplifiers can provide clean sound, but are inefficient, like linear power supplies. Class D amplifiers are similar to switched-mode power supplies and use various pulse modulation […]
Supercapacitor system design considerations
Supercapacitors can deliver more: More power density, more Farads, more cycle life, and so on. But they also demand more complex solutions to realize optimal performance. Among the many design considerations are managing supercapacitor discharge, optimizing supercapacitor charging, and, in the case of series configurations of supercapacitor modules, providing effective voltage balancing between cells. Properly […]
Supercapacitor specifications and IEC/EN 62391–1
When correctly used, supercapacitors can support high power levels, high pulse power loads, and long-term back-up power needs. Understanding the nuances of supercapacitor specifications is the key to maximizing these performance capabilities. There is some level of standardization for supercapacitor sizes, for example, a 10x30mm can supercapacitor is generally 10 Farads across the industry. Some […]
Supercapacitor operation – a higher power source
Thousands of Farads and power densities of thousands of watts per kilogram are among the chief benefits of supercapacitors (also called ultracapacitors). These devices operate in a fundamentally different way compared with conventional capacitors or batteries. Most supercapacitors commonly used today are double-layer capacitors which provide high power capabilities. Pseudo-capacitors are a less common form […]
