RFF series DC-DC converters

Artesyn has launched a series of full brick DC-DC converters designed for use with RF power amplifiers and similar telecom equipment.

The RFF series comprises five 28 V output models, offering a choice of two input voltage ranges and three output current ratings.

All five models feature high power output capabilities and are rated for continuous operation across a wide temperature range, making them suitable for use with high availability equipment used in outdoor environments, such as mobile base stations and last-mile broadband systems. The RFF700 can deliver 25 A at 28 V (700 W), yielding a power density of more than 7.7 W/cm3.

The converters are intended for generating the regulated intermediate bus voltage in telecom systems that use a distributed power architecture. All modules produce a nominal 28 VDC output, which can be adjusted over the range 16.8 to 29.4 V via a single resistor or a suitable control voltage.

The RFF500 and RFF600 have output current capabilities of 17.9 A and 21.4 A and both models are available with a choice of 24 V nominal (18 to 36 V) or 48 V nominal (36 to 75 V) inputs.

The RFF700 handles output currents of up to 25 A and has a nominal 48 V (36 to 75 V) input. All RFF series converters also feature a low voltage (7 to 10 VDC) auxiliary output which can supply up to 20 mA for power control signalling.

A key advantage of the converters is that they can be connected in parallel for high current applications and will automatically share load current, without the need for any additional circuitry. Up to 11 converters can be connected in this manner and by adjusting their output voltages to within 1%, users can obtain up to 95% rated current from each unit.

The converters are based on single forward topology, using ultra-fast recovery output diodes and a high fixed switching frequency of 1 MHz to provide conversion efficiencies of up to 91% at full load.