Innovative high-performance flyback architecture reduces low-power AC/DC losses

Eggtronic has extended its family of high-density power conversion solutions by releasing an ultra-high-efficiency, low component count fixed-output AC/DC converter reference design for applications operating at powers below 120W. The new QuarEgg PSR high-performance flyback solution greatly enhances efficiency and decreases the size of AC/DC converters traditionally used ACF and QR topologies.

Built around the company's patented and proven forced ZVS architecture, the solution supplies a flat idle-to-full-load efficiency curve ranging from 91% at low load to over 94.5% at maximum power. By employing the architecture, designers can greatly reduce total operational losses compared to conventional ACF and QR techniques. Target applications for solution include routers, set-top-boxes, white goods and other low-power applications where efficiency and power density are key criteria, but PFC is not required.

At the heart of the new approach is the company's EPIC QuarEgg PSR IC, a mixed-signal, low-power controller with multi-mode operation and synchronous rectification control that delivers all the necessary primary side regulation without needing an optocoupler. This highly integrated, miniature 5mm x 5mm device includes an optimised low-power mode for enhancing performance at zero and light loads and supplies built-in protection against overvoltage, overcurrent, brownout and extreme temperatures.

"Designers of low-power applications are demanding ever-smaller, higher density power conversion architectures," comments Igor Spinella, Eggtronic's CEO and founder. "We developed the QuarEgg forced ZVS concept to address these demands by providing engineers with a solution that enables high-efficiency low- to high-load operation while reducing overall component count. In our first iteration, we created a PD concept that eliminated the need for a high-voltage, high-side clamping MOSFET, and now we have extended this concept to fixed-voltage solutions that allow us to place an EPIC controller on the primary side and further drive down BoM."