Industrial IoT: Exploring Microcontrollers for Robust Applications

When we think of the Internet of Things (IoT), our imaginations are often limited to consumer applications: smart homes, smart transportation, smart offices, etc. However, these account for just the tip of the iceberg when it comes to IoT. Just beneath the surface lies a sprawling world of industrial IoT and industrial microcontrollers (MCUs).

But just like an industrial solvent requires a formula special and distinct from your ordinary kitchen hand soap, the technical components of industrial IoT devices are starkly different from those that make your smart home HVAC system run smoothly. Nowhere is this distinction more sharp than when it comes to MCUs.

Microcontrollers and Industrial IoT

IoT devices in the industrial world are typically small and unobtrusive – they’re not the star of the show, after all. They incorporate data gathered by sensors from the surrounding environment; information on temperature, humidity, motion, or light exposure, for example. MCUs are responsible for interfacing with these sensors, analyzing the data they capture, and converting it into operational signals that the core technology responds to.

Despite their small size, industrial MCUs play a critical role here. They often form the backbone of automation, controlling and monitoring processes, machinery, and equipment operability. MCUs are frequently employed for motor control – administering speed, direction, and torque of electric motors. This application is critical to running motors with precision and efficiency, and you’ll find it at work in almost every industry: manufacturing, robotics, automotive, and even aerospace.

You’ll also find MCUs utilized in IoT devices that are meant for industrial measurement and instrumentation. These might include multimeters, oscilloscopes, pressure sensors, temperature controls, and flow meters. These measurement applications are incredibly important to energy management systems, in which IoT devices monitor and control consumption, regulate power supply, manage renewables, and optimize efficiency across industrial processes.

MCUs are integral components of industrial safety and security systems, too. You’ll find them used in fire detection and alarm systems, surveillance networks, and intrusion detection devices.

And perhaps the most obvious application of industrial IoT MCUs lies right at your fingertips. MCUs are heavily utilized in developing human-machine interfaces (HMIs) like touchscreens, keypads, and other methods by which you might interact with a given industrial system. HMIs provide control, override, and monitoring capabilities.

The Main Features of Industrial Microcontrollers

MCUs typically have limited processing power compared with the more powerful processors that you might find in smartphones or laptops. But because they are designed as light components with a few, highly tailored functions, they consume less energy and are more efficient in output overall.

This is especially useful in industrial environments, where you may have dozens to thousands of IoT devices operating on a factory floor, for example. These devices need to be equipped to run without interruption for long periods, which means they also need to ensure efficient battery usage and longer product lifecycles.

Durability

Beyond energy efficiency, industrial IoT MCUs are designed with robustness and durability in mind – they are intended to operate reliably in harsh environments (extreme temperatures, vibrations, electromagnetic interference, etc.). And those that respond to temperature often offer a wider range of thermal readings than their consumer counterparts.

Reliability

Engineers who devise industrial IoT devices know they must prioritize reliability, and they subsequently often incorporate redundant features into MCUs to ensure uninterrupted operability. Features to enhance reliability might include watchdog timers, built-in self-test mechanisms, error detection and correction circuits, and fault-tolerant computer architectures.

Communication

Industrial MCUs generally offer a wider range of communication interfacing options than their consumer counterparts, which often rely only on wireless internet or Bluetooth technology. Connectivity options for industrial MCUs can include ethernet, controller area networks (CANs), RS-485, and industrial data communications protocols like Modbus or Profibus, as well as standard Wi-Fi and Bluetooth connections.

Compliance

Industrial microcontrollers are designed to meet certain industry standards and regulatory requirements, ensuring IoT device compliance with safety, reliability, and quality rules. They typically undergo rigorous testing and certification.

Low Latency

Industrial IoT devices need to be able to immediately register and respond to changes in temperature or to a proximity sensor. After all, if the temperature of the machine goes too high and it doesn’t immediately shut off, the result could be a fire or serious damage to parts of the machine. And if a human being gets too close while a machine is operating, that person could get severely hurt unless the IoT device responds instantly to the proximity data and shuts it off. That’s why many industrial MCUs have real-time operating systems, which provide the lowest level of latency. Also, industrial IoT applications commonly use direct peer-to-peer (P2P) connectivity to ensure MCUs are as responsive as possible.

The Five Best Industrial Microcontrollers

Choosing an industrial microcontroller will largely depend on a product’s specific requirements, application needs, and user preferences. But here are five popular MCUs often used in industrial IoT contexts that are known for their performance, features, and industry acceptance.

1. ESP32 series

ESP32 series MCUs from Espressif are typically based on RISC-V or ARM architecture and offer relatively high performance with ultra-low power consumption. They have a wide operating temperature range and versatile functionality. These MCUs feature extensive peripheral sets, including GPIO, UART, SPI, I2C, USB, Wi-Fi, and more. Several in the series also provide substantial on-chip memory (Flash and RAM), advanced timers, and analog-to-digital converters (ADCs).

ESP32 MCUs are well-suited for industrial automation and control systems, thanks to their real-time processing capabilities, rich communication interfaces, and ample peripheral support. They are also a popular choice for low-cost security cameras.

2. LPC Series

LPC MCUs from NXP, such as STM32s, are based on ARM Cortex-M architecture. They’re known for advanced capabilities in handling interruptions. LPCs are consequently often used in factory automation systems that require long-term, uninterrupted operations, assembly line control, process monitoring, etc.

3. PIC32 Series

PIC32 series MCUs from Microchip are based on MIPS32 architecture. Like STM32s, they offer extensive peripheral sets, but also high-speed pulse width modulation (PWM) modules for efficient control of motors, power converters, LEDs, and other IoT device components.

For these reasons, PIC32 MCUs are a great choice for use in motor control systems, like robots, machine tools, pumps, and conveyor systems.

4. SAM Series

SAM series MCUs from Microchip also rely on ARM Cortex-M architecture and are best known for their advanced cryptography and security features. They often integrate hardware accelerators for cryptography algorithms like advanced encryption standards (AES) and secure hash algorithms (SHA). They also support boot functionality, which ensures that only trusted and authenticated firmware is executed during system startup.

For these reasons, SAM MCUs are best applied to industrial IoT devices that require the protection of sensitive data, prevention of unauthorized access, and ensuring the integrity of firmware and communication systems.

5. MSP430 Series

MSP430 series MCUs from Texas Instruments feature 16-bit RISC architecture, and are designed for ultra-low-power applications. Hence, these industrial microcontrollers are favored for IoT devices requiring low-power consumption and efficient processing. You’ll find MSP430 MCUs in many battery-powered industrial IoT devices, as their signature energy efficiency promotes battery conservation and long product lifecycles.

Final Thoughts

There are numerous MCU options on the market for industrial IoT devices. As we’ve discussed, many offer distinct features and are ideal for different applications. Hopefully, armed with the information explored in this post, you now have a foundational understanding of how different MCU series may or may not meet your specific needs. 

But the options detailed above are just a sampling of what’s out there – rest assured that for nearly every industrial context imaginable, there’s an MCU that will work for you. Good luck.