Rugged high-density AC/DC FEMs feature isolation and power factor correction

Vicor has introduced new family of high-density PFM AC/DC front-end modules (FEMs) in rugged VIA package that offers superior cooling performance and versatility in converter mounting. Featuring a universal AC input range (85 - 264VAC), power factor correction, and a fully-isolated 24VDC or 48VDC output, and delivering 400W of regulated DC output power at efficiencies up to 93%, the new modules provide unprecedented power density of 127W/in3 (8W/cm3) and best-in-class performance in a diminutive, 9mm thin VIA package. The new units are ideally suited for use in a broad range of industrial, process control, telecommunications, office equipment, test and measurement, LED lighting and other 'off-line' applications. Every electronic product or system that operates off of an AC utility line must incorporate an AC-DC "front end" to convert the AC utility voltage into the smooth DC voltage required by electronic circuitry. These new units integrate a full range of front-end functions required by contemporary AC line-operated power systems - transient and inrush current protection; input power factor correction; input to output isolation; and a regulated SELV (Safety Extra Low Voltage) DC output - and meet international safety and regulatory agency standards for isolation, conducted emissions, power factor correction, and susceptibility to AC line transients, flicker, interruptions and surges. VIA package configurations are available for both on-board mounting and chassis mounting and units are available in two operating temperature ranges. In many applications, a user can instantly implement a complete AC-DC front end by simply combining a PFM with an AIM (Universal AC Input Module), which integrates all required primary-side rectification, filtering and transient protection circuitry), both in VIA packages and suitable secondary-side storage capacitance. Alternatively, a designer can combine a PFM front-end module with rectification, filtering and secondary-side output capacitance that is optimised for a specific application. In either case, the PFM front-end module offers a quick and easy pathway to a rugged, high-performance, high-density AC-DC front-end solution, while eliminating the uncertainties and long design cycles associated with a custom front-end design. And, whereas many alternative front end systems are configured with capacitive energy storage at the high-voltage input, the PFM offers enhanced system safety by storing energy in low voltage capacitors at the isolated SELV output. At one-fifth the thickness of traditional "1U" front-end solutions, the mechanically robust, thermally adept VIA package simplifies mounting to an equipment side panel, chassis or other external heat sinking device and provides improved thermal performance in any application. Moving the AC-DC conversion function to a chassis or side panel can reduce system size and cost, or free up valuable system real estate for other uses, and can provide improved thermal performance while eliminating the need for, and cost of, external heat sinks, says the company.