Recom Intros 2 SMD Transformer Families for DC-DC Conversion

Recom has expanded beyond complete DC-DC converter modules with the introduction of its RMR and RBE series SMD transformers, giving engineers the option to build discrete isolated power supply designs using Recom driver ICs and matched transformer solutions.

The transformer families are designed for isolated DC-DC converter applications ranging from 1 W to 30 W and support several common converter structures, including push-pull, full-bridge, and flyback designs. By offering both transformer driver ICs and matched transformer components, Recom is targeting engineers who want greater flexibility in PCB layout, thermal design, and component placement, and scaling costs at higher production volumes.

The RMR and RBE transformer families are designed to support discrete isolated DC/DC converter designs with isolation ratings up to 5 kVAC. Image used courtesy of Recom

Two Transformer Families for Different Power Architectures

Recom’s product lineup comprises two transformer families, the RMR and RBE series. While both are designed for isolated DC-DC converter applications, they target different converter configurations and power levels.

The RMR series focuses on lower-power push-pull and full-bridge designs in the 1 W to 2 W range using compact toroidal transformer constructions. These parts are designed to pair with Recom’s RVP series transformer driver ICs and support applications requiring compact isolation solutions with relatively small PCB footprints.

The RBE series targets higher-power flyback converter designs ranging from roughly 6 W to 30 W. These transformers use bobbin-style construction and are intended for use with Recom’s RVPW flyback driver ICs.

Compared to the RMR family, the RBE series is aimed more at industrial and higher-power isolated supply applications that require increased output power and larger voltage ranges. Both series are available in surface-mount form factors and are designed to tolerate standard SMT manufacturing conditions, including reflow temperatures up to 250°C.

RMR Series Targets Compact Isolated Power Designs

The RMR series features a toroidal SMD transformer design intended for push-pull and full-bridge converter systems. These transformers cover a range of common voltage combinations, including 3.3 V, 5 V, 12 V, 15 V, and 24 V configurations, making them suitable for a broad range of low-power isolated supply designs.

Isolation ratings across the RMR series range from 1.5 kVDC up to 4.5 kVDC, depending on the model. Higher-isolation versions, including the RMR-028 and RMR-031, increase that rating up to 5 kVAC while also using larger creepage and clearance spacing. These parts are intended for applications that require higher levels of electrical isolation or additional safety margins.

Push-pull DC/DC converter design using Recom’s RMR-003 transformer. Image used courtesy of Recom

Physically, the RMR family remains relatively small, with some package sizes measuring roughly 8.1 × 6.8 × 3.8 mm. Even with the compact dimensions, the transformers are designed to support standard SMT assembly processes, including dual reflow capability. Recom has also paired many of the RMR transformers with open-frame reference DC-DC converter designs, allowing engineers to evaluate complete power architectures using matched driver IC and transformer combinations.

The lower-power focus of the RMR series makes it suitable for applications such as industrial control electronics, isolated communications interfaces, gate drive supplies, sensor isolation, and embedded power rails where compact isolated conversion is required but board space remains limited.

RBE Series Expands Into Higher-Power Flyback Designs

The RBE series is suitable for higher-power isolated DC-DC designs that use flyback converter arrangements. These transformers can support power levels from approximately 6 W up to 30 W and are intended for use with Recom’s RVPW flyback transformer driver IC family.

Compared to the smaller toroidal RMR parts, the RBE transformers use bobbin-style construction and support a wider range of input voltages and output configurations. Several models are designed around 24 V and 48 V input systems commonly found in industrial automation, transportation, telecom, and distributed power architectures.

Example of a flyback converter implementation using the RBE-011 transformer. Image used courtesy of Recom

Isolation ratings across the RBE family range from 1.5 kVDC up to 6 kVDC, depending on the specific model. Certain versions also include expanded creepage and clearance spacing for applications requiring increased electrical isolation. Recom also introduced specialized variants such as the RPE-026, designed for bidirectional battery cell charging and discharging applications using the company’s synchronous rectifier controller platform.

The larger power capability of the RBE lineup allows the transformers to support more demanding isolated power applications, including distributed industrial power rails, embedded auxiliary supplies, battery management systems, and higher-power control electronics. Several open-frame reference converter designs are also available for the RBE family, providing engineers with validated starting points for discrete converter development.

Recom’s RMR and RBE transformer families expand the company’s isolated power portfolio beyond complete converter modules and into discrete DC-DC power design. By offering matched transformer driver ICs alongside compact SMD transformer solutions, Recom is giving engineers more control over layout, thermal management, isolation design, and system optimization.

With support for multiple converter configurations, power levels from 1 W to 30 W, and isolation ratings up to 5 kVAC, the new transformer families are positioned to support a wide range of industrial and embedded isolated power applications.