Configurable power supply outputs up to 1200W from 1U profile

September 15, 2016 // By Graham Prophet
XP Power's nanofleX series of configurable digitally controlled AC-DC power supplies has a compact low profile 1U mechanical chassis format that suits today’s space constrained designs and can accommodate up to four single-slot plug-in customer selected output voltage modules.

Designed to maximize efficiency and minimize audible fan noise, the nanofleX series can deliver up to 850W from a universal input voltage or up to 1,200W from a high line source. The four output module slots provide nineteen nominal output voltage options in the range + 3.3 to + 60 VDC. Outputs are derived from one of four base, digitally controlled, modules that each span a wide voltage adjustment range. This approach provides ultimate flexibility and user adjustment to tailor the product to the end application and supports fast turnaround delivery of products configured to exact user requirements, from stock held in several XP Power locations worldwide.


The architecture of the supplies uses a three-stage switching layout. The universal AC/DC front end has a bridge-less, interleaved power-factor-correction input that uses 65kHz switching. The primary switching, LLP resonant stage runs at around 120 kHz and employs a single, planar isolation transformer. Rather than rectifying the transformer output to a single intermediate bus, the secondary windings of the isolation transformer are available to each output module, and plug-in selection connects the secondary taps appropriate to the individual output selected. Each output module carries out synchronous rectification of the isolation transformer feed, followed by a 250-kHz switching buck or boost conversion to the final output. XP chose to offer a four-output format as its research indicated that the great majority of typical applications require three or four rails.


Cooling fans are positioned in the centre of the product further reducing audible noise and allowing users to specify the airflow direction to suit their application. The full output power rating is available regardless of airflow direction.


The nanofleX platform supports both analogue and digital control, although the conversion control loops within the supply are analogue; the main regulation function is on the primary side of the main converter. The analogue signals include AC OK (global), DC OK (global and local module)