Enabling Efficient Power Consumption in IIoT Applications

Brandon Becker, Technical Product Marketing Manager, ROHM


With increasing demand for higher efficiencies in manufacturing processes and stringent health and safety requirements, Industrial Internet of Things (IIoT) systems are becoming more commonplace.

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Figure 1: Industrial Internet of Things is being integrated into many modern manufacturing processes

Offering a wide range of benefits, including greater reliability, enhanced safety, minimal downtime, enhanced productivity, and cost-effectiveness, IIoT is becoming critical to the manufacturing industry. However, power consumption is a key concern in IIoT systems. For example, remote monitoring and real-time data analytics require increasing amounts of power from energy sources such as power grids, batteries, and energy-harvesting devices. Consequently, engineers must develop innovative solutions to ensure efficient power consumption. This whitepaper explores the latest IIoT trends and power challenges and outlines ROHM’s power solutions for IIoT applications.

Latest IIoT Trends in the Manufacturing Sector

Manufacturers have been increasingly incorporating IIoT solutions into their everyday processes. The most common IIoT applications such as smart factories and automotive assemblies utilize transducers, sensors, and actuators to make processes more “intelligent.” In addition to scaling up operations, IIoT offers greater flexibility, reliability, and safety, which translates to an improved bottom line in several industries. Some of the latest trends in IIoT include predictive maintenance, remote monitoring, sensor technology, digital twin technology, health and safety compliance, and industry 4.0. With predictive maintenance, manufacturers automatically detect possible machine failures before they occur, while remote monitoring using sensor technologies allows for real-time decision-making. Similarly, digital twin technology facilitates remote access of devices and equipment on today’s factory floors, forecasting, as well as predictive maintenance to minimize costly downtime on operations.

In light of the COVID-19 pandemic, manufacturers are also leveraging IIoT to ensure health and safety compliance within the workforce. For example, electronic sensors can track employees’ location on the factory floor and monitor their vital signs via temperature sensing. Industrial operations have undergone rapid development throughout the years with Industry 4.0 as adoption of IIoT can meet specific needs of different industries. Organizations are improving their customer experience, strategies, revenue streams, and process efficiency using IIoT.

In hotel and hospitality, managers can integrate IIoT equipment into meeting the needs of their guests to give them a higher-rated experience during their stay. Similarly, the mining and energy industry can enhance the safety of employees and assets at both onshore and offshore locations with IIoT. Mining operations, for instance, are safer with gas sensors that can detect gas leaks as soon as they happen for early evacuation of the mine, or to detect the likelihood of mine shaft failures.

The Basis of Power Optimization in IIoT Applications

Although grids power many of these applications, low-voltage systems utilizing remote sensors rely on portable energy storage such as batteries and supercapacitors. Since there is limited power for charging, there is a need for efficient power consumption in IIoT applications. Various existing and innovative power solutions enable efficient power conversion in IIoT systems, which, in turn, reduces power dissipation and extends battery life. These solutions are critical for preventing loss of production, equipment malfunction or damage, costly downtime, and high annual maintenance costs. Moreover, optimized power solutions allow engineers to design high-performance, reliable, and miniaturized IIoT devices.

The Industrial Internet of Things (IIoT) is composed of four key layers, including the sensing layer, communication layer, application layer, and management optimization layer, as shown in Figure 1. These layers work together to achieve improved operations in industries. Management optimization ensures the efficient utilization of power in the overall system, amongst other functions. Other layers require a specific amount of power to function optimally. Consequently, designers must incorporate robust power solutions into IIoT systems.

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Figure 2: Cycle of Industrial Internet of Things


Several critical elements of IIoT devices, such as accelerometers, wireless communication modules, buck converters, and microcontrollers (MCUs), require high power conversion efficiencies with lower power dissipation. Similarly, miniaturized devices require high-energy efficient MCU integration. Although computational needs affect the selection of 8-bit or 32-bit MCUs, engineers must consider the energy requirements to achieve optimum results. The choice of buck converter directly affects the overall power consumption of IIoT devices.

Engineers can opt for a light load efficiency range of <10μA, which offers excellent transient response and extends battery life via lower power dissipation in the intended application. Other essential parameters include operating temperature range, quiescent current, input voltage range, and switching frequency levels. Some OEMs deliver converter solutions with Ultra Low Power (ULP) mode. Figure 2 shows how a ULP mode-integrated converter switches from normal to ULP mode for voltage monitoring and power saving. Designers can integrate the IC with two comparators: the main comparator and the ULP comparator. A decrease in VOUT will induce high impedance and subsequently trigger the transition from normal to ULP mode.

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Figure 3: Switching between Normal and ULP Modes


Selecting accelerometers with low power usage is critical in IIoT applications. Advanced functions, such as signal conditioning and intelligent user-programmable application algorithms in accelerometers, ensure efficient sensing in IIoT systems while maintaining low power operation. As input current is a function of an accelerometer’s output data rate (ODR) and power mode settings, engineers must consider the ODR before incorporating it into an IIoT system.

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Figure 4: The relationship between current and accelerometer ODR


ROHM’s Power Solutions for IIoT Applications

It is often believed that incorporating Wi-Fi or cellular networks into IIoT applications is more energy demanding compared to Bluetooth-based networks. With recent developments in wireless communication modules, engineers can now incorporate low-power consuming wireless technologies into IIoT systems. These modules offer high radio frequencies with low current consumption, allowing engineers to integrate power-optimized devices into IIoT applications. ROHM’s low power solutions for IIoT systems include KX13x accelerometers, BP35C wireless module, BD70522 DC/DC converter, 16 and 32bit MCUs, and low-current chip LEDs.

ROHM is a member of the Wi-SUN Alliance, a global certification association providing communication solutions for large outdoor networks. Wi-SUN Alliance enables a diverse ecosystem of solution providers, including product and silicon vendors, cities, utilities, government institutions, and academia building smart solutions. It offers a robust certification program ensuring interoperability in wireless devices for outdoor Field Area Networks (FAN), Home Area Networks (HAN), and other IoT networks. Some key applications include the following:

●      Smart utilities: Advanced Metering Infrastructure (AMI), peak load management, distribution automation, and smart metering.

●      Smart cities: Street lighting, infrastructure management, smart parking, environmental sensing, traffic, and transport systems.

●      Smart home: Smart thermostats, air conditioning, heating, energy usage displays, and health and well-being applications.

●      M2M: Agriculture, structural health monitoring (e.g. bridges, buildings, etc.), monitoring, and asset management.

ROHM’s KX132-1211 and KX134-1211 accelerometers offer a high sensitivity range of ±2g to ±64g to meet several sensing needs in IIoT applications. These solutions feature power-saving capabilities such as wake-up and back-to-sleep detection, significantly minimizing power consumption during idle periods. Similarly,ROHM’s compact wireless communication module can network up to 1000 units, offering extensive area coverage by incorporating it into social infrastructures such as traffic and street lights. The BP35C is a WiSun FAN module for secure communications between IIoT devices within a network. Offering in-built security features, it enables high-efficiency power utilization at an ultra-high radio frequency band of 920 MHz.

ROHM’s BD70522GUL is ideal for battery-powered IIoT systems and offers input voltages from 2.5V to 5.5V. The buck converter offers Constant ON-Time (COT) control, ultra-low power mode, exceptional transient response, and extends battery life with its light load efficiency. It also features a programmable output voltage range of 1.2V to 3.3V using VSEL pins, as well as a small-footprint VCSP50L1C package that minimizes inductance and heat dissipation. Moreover, the ML620Q500 16bit and ML630Q400 32bit MCUs are low-power high-performance solutions that achieve high efficiency in IIoT applications with advanced capabilities. These products are well suited to battery-driven applications due to their support for low-voltage low-power applications. ROHM also offers a chip LED lineup comprising high power type, rear mount type, side-emitting type, and compact type.