A new 8:1 non-isolated bus converter introduced

Flex Power Modules has released the BMR320, a non-isolated, unregulated, DC-DC intermediate bus converter with a fixed 8:1 input/output voltage ratio in a compact form factor.

The product functions over a 40-60VDC input range, producing a 5VDC to 7.5VDC output, excellent for powering point of load converters at lower intermediate bus voltages to optimise system efficiency. The device is rated at 400W/60A at 54V input and delivers an exceptional power density of 128W/cm3 (2126W/in3), measuring only 27mm x 18mm x 6.4mm. With efficiency peaking at 97.7%, up to three units may be paralleled for a complete load of 1080W. The parts are developed for topside cooling to a heatsink with airflow or liquid cooling through a thermal block. The relatively flat design of the topside of the converter permits easy connection through a thermal interface material such as a gap pad.

The unregulated, non-isolated architecture used in the device lowers the output impedance of the converter when compared to regulated designs, which effectively mirrors the input bus capacitance efficiently to the output, improving its capacity to cope with large load transients with minimal 'droop'.

The protection features include output current limit, over-voltage, over-temperature, and input undervoltage. A PMBusTM interface is included for monitoring and control, and the part is supported by the Flex Power Designer Tool.

Anders Sellin, strategic product manager at Flex Power Modules, comments: "The BMR320 intermediate bus converter is designed for optimum system efficiency when used alongside point of load converters and integrated power stages such as our BMR510 and upcoming BMR515. It is a great solution for datacom, cloud computing and AI applications, where power density, efficiency and low cost are critical factors."