This is the final part of a three-part series discussing measurement methods for high-frequency, common-mode (CM) current, voltage, and impedance using a flyback converter. Part I covered the basic principles of radiated EMI and the traditional method for measuring CM current in a flyback converter topology. Part II explored a ferrite bead solution for CM current measurement errors and how to obta...

This is the second part of a three-part series discussing measurement methods for high-frequency, common-mode (CM) current, voltage, and impedance using a flyback converter. Part I covered the basics of radiated EMI and the traditional method for measuring CM current in a flyback converter topology. Part II will propose a solution to common errors when measuring CM current, and then it will demons...

The low-carbon era is leading the development trend for smaller and highly efficient chips. First, switching power supplies replaced linear power supplies in the 1980s; now, the efficiency of power supplies has significantly improved while the overall solution size has been reduced. When considering consumer requirements for portability, switching power supplies continue to become more and more ad...

To meet the increasingly stringent requirements for environmentally friendly solutions, MPS’s AC/DC power supply products utilize advanced technologies to enhance performance and achieve energy conservation. This article is the second in a two-part series to discuss trend-setting AC/DC solutions. Part I served as an introduction for the carbon-free era and the problems that designers face with tr...

To obtain an accurate EMI analysis when modeling power electronics, it is crucial to measure the impedance on the noise source and propagation path. For radiated EMI, the corresponding frequency band is typically between 30MHz and 1GHz. Due to the high frequency, it can be difficult to measure parameters such as voltage, current, and impedance. This article is the first part of a three-part serie...

MPS is committed to providing users with a variety of simulation solutions, including SIMPLIS models, SPICE models, DC/DC converter design models, and Virtual Bench Pro. The easy-to-use Design Assistant is the most popular tool provided by MPS, and its demand continues to grow each year. Figure 1 shows the annual growth of how often our Design Assistant is requested and utilized. In partic...

The flyback power supply is one of the most commonly used topologies. Typically, the transformer’s leakage inductance causes primary-side ringing, which generates voltage spikes that damage the MOSFET. It is essential to design the transformer and MOSFET components to control ringing. MPS has introduced an RCD clamp circuit design strategy to reduce leakage inductance. This circuit is described in...

This article is the second part of a two-part series exploring how to design an active-clamp forward controller for PoE-bt applications. Part I covered PoE applications, as well as the basics for forward converter topologies and active clamps. Part II will review secondary-side synchronous rectification MOSFETs, secondary spike absorption circuits, and efficiency verification processes for PoE-bt ...

When compared to traditional AC power supply modes, power over Ethernet (PoE) power supplies can simultaneously supply power and transmit data through an existing Ethernet cable. By integrating the power supply and data cables, PoE applications are cost-effective and provide flexible installation. PoE solutions are rapidly growing in popularity across multiple industries as applications continue t...

Flyback power converters are currently some of the most common converter topologies around. This is due to the simplicity of their design and the competitive size/cost/efficiency ratio their can deliver, especially in the mid-level power range (2W to 100W). Like any converter topology, a flyback converter is composed of a power path and a control path. The power path is responsible for the conver...

For battery-powered applications, an excellent user experience depends on a long battery life and high-performance terminal devices. Quiescent current (IQ) is an important parameter to consider when optimizing these applications; in particular, an improved IQ increases battery life. This article will describe the difference between a boost converter’s IQ and shutdown current (ISD) to provide a de...

In June 2022, the EU parliament approved a mandate that will require the next generation of portable devices to be compatible with USB Type-C charging connectors. Manufacturers have until fall 2024 to make their products compatible with USB Type-C cables by adding a USB Type-C connector. Affected industries include mobile phones, digital cameras, handheld video game consoles, portable speakers, ke...

Rotary dials are used in diverse applications for human-machine interfaces (HMI). Touch interfaces include the buttons, knobs, and dials on everyday devices, from automobiles and white goods, to the touch screen on your mobile phone. These devices not only translate human input into an electrical signal, but they also provide an important feature — haptic feedback. This is especially useful for sa...

The design requirements of today’s switching power supplies are driven by efficiency requirements not only at full load, but also under sleep mode or no-load conditions when the cable is disconnected. Power system integrators have to meet new regulations from agencies such as Energy Star, 80 Plus, and the European Commission’s CoC, regardless of the power supply’s load condition....

The new surface-mounted power inductors from Monolithic Power Systems are designed for applications ranging from power supplies to power converters. The molded and semi-shielded series inductors include inductance ranges from 0.33µH to 22µH, and saturation current ranges from 0.8A to 64A. This series includes molded, magnetic-shielded power inductors that offer soft saturation due t...

The 5G telecom standard is intended to support the ever-increasing data volume requirements from smartphones and smart connected devices in markets such as home and industrial automation, autonomous vehicles, healthcare, and smart wearables. 5G enables many more data connections per base station by using what are called “massive multiple-input multiple-output” (massive-MIMO) antenna ar...