by Leland Teschler, Executive Editor, @DW_LeeTeschler Does it really take a voodoo practitioner to design a switching power supply? You might think so judging by the “black art” label that’s often applied to this aspect of power electronics. The reputation for witchcraft here comes in large part from the role magnetic materials play in getting […]
Power Electronics Handbook
Teardown: What’s inside a Phillips Sonicare electric toothbrush
by Leland Teschler, Executive Editor A novel ac rectification and coil-driving scheme may characterize the electronics found in this widely used oral hygiene instrument. The Philips Sonicare Elite series toothbrush is billed as generating over 31,000 brush strokes per minute thanks to “sonic motion” driving its brush. A teardown reveals what Philips is talking about […]
Driving LEDs with SiC MOSFETs
by ADAM BARKLEY, SiC Power Device Application Engineer, Wolfspeed, a Cree Company and VIPINDAS PALA, Research Scientist Wolfspeed, a Cree Company Engineers increasingly see the logic of silicon-carbide MOSFETs for handling a lot of electrical power, but new SiC devices also make sense for high-voltage switching. The benefits of silicon-carbide power MOSFETs are becoming widely […]
Coin Cell dimensional tolerance and battery holders
Competing brands of batteries can have substantially different dimensional specs. Where this dimensional tolerance has an impact is in the battery holder. A coin cell holder must be designed so it can handle normal height variances while at the same time, not accept batteries of a different type. Obviously, the battery holder can’t have a […]
Power converters with GaN
by Alex Lidow, CEO, Efficient Power Conversion Corp. It can be tricky to analyze power supply designs incorporating GaN power devices. Here are the basics of calculating losses and device currents when using these exotic semiconductors. There is a lot of activity in wide-bandgap semiconductors these days. They have the ability to operate at much […]
High switching frequencies come to laptop chargers
New designs for switch-mode power supplies are pushing frequencies higher as a way of cramming circuitry into smaller and smaller volumes. An indication of the trend can be seen from the recently developed Dart power supply from Finsix, a start-up with roots in the Massachusetts Institute of Technology. The Finsix device fits in the palm […]
Move over, wave power — Vortex device aims to harvest energy from water
Pilot projects aimed at generating electrical energy from the motion of ocean waves have gotten a lot of press. The Scottish government, for example, has now approved the installation of a 40-MW wave energy generation facility in the Shetland Islands. To these efforts you can now add those of a company called Vortex Hydro Energy […]
Better barriers make lithium batteries hard to beat
An advanced barrier between the electrodes in lithium-ion batteries could help head off fires and overheating that occasionally arises in laptops or industrial applications. The barrier uses nanofibers extracted from Kevlar. The barrier helps minimize the growth of metal tendrils on battery electrodes that can otherwise lead to electrical shorts. In normal battery operation, there […]
Gallium Nitride power FETs go into mass production
Fujitsu Semiconductor group’s CMOS-compatible, 150-mm wafer fab in Japan has started mass production of Gallium Nitride (GaN) power devices for switching applications. The facility is providing GaN foundry services for Transphorm, which has established the only qualified 600-V GaN device platform. The first photovoltaic power conditioner products using the GaN module from Transphorm also launched […]
Power supply makers get ready for tighter energy efficiency regs
Tougher Energy Star standards kick in next year. Some manufacturers may not be able to handle its more stringent mandates. The latest round of energy efficiency standards for external power supplies will go into effect next year. But unlike previous standards, efficiency levels dictated by the new mandates, which power supply makers dub Level 6, […]