DC/DC Converters for RF Systems Reach up to 93% Efficiency to Support 5G/6G

18 November 2025  

Flex Power Modules has announced it has expanded its PKU-D range with two high-efficiency DC/DC converters – the PKU4911D and PKU4917VD – designed for low power radio-frequency power amplifiers (RFPAs) and microwave applications. The additions strengthen the PKU-D family of analog-controlled DC/DC converters in a sixteenth-brick format suited to the size and thermal limits typical of dense RF and telecom boards.

The PKU4911D is a 5 V nominal (4-5.5 V adjustable), 100W converter with a 36‑75 V input range. Typical efficiency is 93% at 48 V input and full load, reducing heat losses and helping engineers stay within thermal limits in compact RFPA assemblies. It provides a stable, low-noise output (2% max) for RF and microwave stages where voltage stability and ripple are critical performance factors.

The PKU4917VD is a 6 V nominal (5.5-6.6 V), 100 W converter in the same sixteenth-brick PKU-D form factor and accepts 36‑60 V input. Efficiency reaches 92.7%, helping reduce heat and ease cooling requirements. The 6 V rail provides a stable intermediate voltage that can directly power driver and control circuits efficiently.

 Validated thermal models are available for both modules to speed derating decisions and heatsink/airflow sizing. Sharing the established PKU-D footprint allows design teams to reuse board layouts across voltage options with minimal modification, shortening development cycles for 5G/6G network microwave links, satellite communications and radar equipment.

 “In RF and microwave systems, managing heat effectively is just as critical as saving space,” said Olle Hellgren, Director, Product Management & Marketing at Flex Power Modules. “By offering 5 V and 6 V options at around 93% efficiency in a sixteenth-brick format along with ready-to-use thermal models, engineers are empowered with practical solutions to reduce design cycles and time to market.”

Both modules comply with telecom and industrial safety standards for isolated DC/DC converters, with 2250 V input-to-output isolation for use in RF/microwave equipment. They are approved to IEC/EN/UL 62368-1 safety requirements and are suitable for use in high-reliability infrastructure such as 5G/6G microwave links, satellite and radar systems.

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