AC/DC open-frame PSU outputs 40W from 4.5 sq in footprint

October 12, 2016 // By Graham Prophet
XP Power's ECF40 series of single-output 40W ultra compact AC-DC power supplies are open frame convection-cooled units capable of delivering theie full output power without the need for any external forced air flow up to +50C.

XP claims the units as the smallest 40W open frame power supply available, at 76.2 x 38.1 x 28.0 mm. The company says its market research indicated a need for a PSU of this power level, with full medical approvals, in the smallest possible outline – including not compromising profile (height). XP intends the unit for a range of applications in the healthcare, industrial and technology sectors, rating it for an operating temperature range of -40 to +70C (no derating until 50C). The footprint space required in the end system with the ECF40 is 44% smaller than competing products with a standard 2 x 4 in. size, and 25% smaller than the current smallest known product. The range comprises six models providing all the popular nominal output voltages from +12 to +48 VDC. The voltage on all models can be manually trimmed ±10% via a user accessible potentiometer on the supply.

 

The series consumes less than 0.15W during no load conditions helping designers ensure their end product can comply with the most recent energy efficiency standards. With a high typical efficiency of 90% or higher, the very flat efficiency curve ensures that the ECF40 consumes less energy than other similar supplies available on the market and runs cooler. XP adds that it has achieved the small dimensions and efficiency with a relatively conventional architecture; the supply uses a bridge rectifier on the AC input, and synchronous rectification on the secondary side. The company also believes that the small size has not impacted reliability, and that it has rated components (especially electrolytic capacitors) conservatively for long life (a 3-year warranty is standard).

 

The ECF40 series is certified to the ITE IEC/UL/EN 60950-1 and IEC/EN60601-1 / ANSI/AMMI ES60601-1 3rd edition medical safety standards, features 4000 VAC input to output isolation, two AC line fuses, a maximum of 250 µA leakage current and provides two means of patient protection (2