Power Solutions for the Internet of Things (IoT & IIoT)

The Internet of Things (IoT) is an umbrella term encompassing many related concepts, all of which share common features: distributed intelligence, multiple interconnected sensors and actuators, and decentralized control. In practice, IoT enables spaces, environments, or objects to become “smart” by incorporating sensors that communicate to operate intelligently. Examples include offices that adjust to ambient light or human presence, machines that monitor their own health, and homes that learn daily routines to save energy automatically without compromising comfort.

All of this technology requires power: highly efficient, low-standby AC/DC power supplies for smart offices with hundreds of intelligent sensor nodes, energy harvesting solutions, or compact, cost-effective DC/DC power modules. Not all power supplies are suitable for IoT applications. They must be highly efficient at both low and full load, handle fast transient and dynamic load currents, be physically compact, reliable, and affordable, as they will be as ubiquitous as the sensors, processors, radios, and actuators they power. This is why RECOM developed next-generation 3DPP® DC/DC power modules such as the RPMx, RPX, and RPL – miniature low-profile SMD power supplies delivering up to 17W while occupying 1cm² or less board space – and the RxxCTxx, which provides 5kVAC isolation in a 2.6mm-high package.

The industrial internet of things is a subset of IoT, relating to interconnected sensors, instruments, and other devices used in the commercial manufacturing and energy environments. Leveraging IIoT promises improved process efficiency, productivity and safety, while allowing better decision-making and predictive maintenance to reduce downtime and operational costs.

The industrial environment can be challenging for electronics, but standard RECOM AC/DC and DC/DC converters are an excellent solution thanks to their wide temperature ratings, high efficiency, robust construction, long warranty, and low acquisition and lifetime cost. Many standard RECOM AC/DC products are particularly suitable for noisy industrial environments with their Over Voltage Class III (OVCIII) input rating. Parts are also available with nominal input ranges that include 277VAC for line-to-neutral connections in industrial 480V three-phase systems, or rated up to 480VAC for line-to-line three-phase configurations.

As with general IoT applications, Industrial IoT demands low standby power losses, comprehensive protection features, and minimal EMI emissions—all of which come standard with RECOM industrial power supplies. Many products also have safety certifications suitable for commercial applications, particularly EN 60335-1 as well as EN 62368-1 and EN 61010.

IoT will be ubiquitous, requiring many small AC/DC supplies to power sensor networks. The RAC series offers cost-effective, compact, efficient low-power supplies ideal for IoT installations. They have low standby power requirements yet deliver up to 175% peak load, operate from all standard AC voltages, and are fully certified to worldwide standards, including the 60335-1 household norm (RACxx-GA).

In large US office buildings, lighting supplies often run from a 277VAC source. The RAC-SE series offers an extra-wide input range of 90-305VAC, supporting intelligent lighting and smart office/building applications. The RAC03-SER features a unique round shape only 11mm thick, allowing mounting inside a standard wall box behind a socket or switch plate. The SE series is IEC/EN/UL safety certified for industrial and household applications.

The RAC05-SK/C14 is as easy to mount as a mains filter but functions as a full power supply. It includes an IEC mains input connector (kettle plug), accepts 85VAC to 264VAC, and provides a safe, short-circuit-protected DC output of 3.3, 5, 12, 15, or 24VDC. The standard die-punch mounting holes allow quick installation with just two fixings. The 5W output is sufficient to power single-board computers such as Raspberry Pi, Arduino, and BBC Micro:bit, as well as IoT nodes, sensors, and relay stations. Typical industrial applications include IoT mesh networks, 19” rack-mount equipment, short production runs, or mass production.

Industry 4.0 is driving smart factories that communicate to accelerate manufacturing. As sensors, actuators, drives, and control nodes increase, secure and reliable interactions are critical. RECOM offers low-profile, cost-effective DC/DC converters for IoT applications, including boost and buck switching regulator modules designed for very low-power needs.

The RPMx family uses the same LGA case and footprint, providing performance options (higher input voltages or output currents) and upgrade paths within each family. RPMB versions offer 2A or 3A outputs, allowing design upgrades without changing PCB layouts.

The RPX family uses the same QFN footprint, with maximum output currents of 1A, 1.5A, 2.5A, or 4A and input voltages up to 36V. These converters integrate FET switchers, power inductors, and controllers into a complete SMD power supply in a 5mm x 3mm x 1.6mm package.

The RPL modules provide up to 3A output in a tiny LGA10 3mm x 3mm x 1.45mm package. Integrated FET switchers, power inductors, and controllers form a complete SMD solution for input voltages up to 18V with output adjustable from 0.8V to 5.2V.

The R05CT05S is an isolated DC/DC converter in a 16-pin SOIC package (10.3mm x 10.3mm x 2.65mm). Its coreless transformer provides 5kVAC reinforced isolation and a pin-selectable 5V/100mA or 3.3V/150mA regulated output, with an operating range from -40°C to +140°C.

The R1SX are thumb-sized SMD DC/DC converters isolating 3.3V and 5V supplies to separate control functions, preventing local faults or interference from causing system-wide outages. Despite their small footprint and 6mm profile, they offer 3kV isolation, full-power operation from -40°C to +100°C, and high efficiency, suitable for bus isolators, industrial controls, and battery management systems.

The R-78S switching regulator is designed for single-cell IoT applications. With a wide input range, high efficiency, and low standby losses, it extends battery life while maintaining stable 3.3V output down to the lowest battery voltage. Based on the R-78 buck regulator plug-and-play concept, the R-78S boost regulator provides stable 3.3VDC from inputs as low as 0.65V, powering IoT nodes, Bluetooth sensors, or LoRaWAN transmitters.

RECOM’s R-78S evaluation board lets engineers test the R-78S regulator, boosting a AA battery or external supply to 3.3V for low-power IoT applications. Jumper headers measure input/output current and voltage, allowing battery lifetime calculations in active and standby modes.

The R-REF02-78S is a ready-to-use 3.3V IoT design, generating 3.3V from a single AA battery. The reference design includes a battery holder and R-78S3.3-0.1 boost converter. Jumpers J1 and J2 connect to the output voltage and CTRL pin. An enable pin puts the R-78S into sleep mode, drawing only 7uA from the battery.