Our world is getting smarter each day. Connected home systems make our personal sanctuaries safer and more comfortable. Industrial sensors keep manufacturing lines up and running continuously, while enabling equipment to adapt to product changes. Wearables and hearables monitor health parameters while providing an array of other functions.
Wireless, battery-powered IoT devices are a substantial driver in the overall growth of the IoT market, especially in areas such as industrial, agriculture, utilities, logistics, and smart cities. In many of these environments, changing the batteries in these devices is difficult due to their location and/or distribution across a wide area. As such, battery life ends up dictating the lifespan of the devices, so the longer the battery life, the better.
Wireless, battery-powered IoT devices used in applications such as smart cities are a substantial driver in the overall growth of the IoT market.
Portable IoT devices share another common factor: they're part of a growing segment of smart, connected applications that requires more microcontroller units (MCUs) as they become more advanced. For example, advanced IoT systems typically include a:
- Dedicated processor to manage the application
- Processor serving as a sensor hub
- Bluetooth
Low Energy (BLE) MCU for handling the wireless connectivity function
Often, a power management IC (PMIC) is included in the mix to provide supply voltages to the MCUs. The challenge is, as these devices are expected to do more, they're also expected to get smaller. Long battery life is a big demand—consumers prefer infrequent battery charging and, as noted, changing batteries for sensor nodes in certain designs can be quite labor-intensive. Ultimately, adding more components to the design to increase functionality is clearly not a sustainable approach.
An MCU designed with the unique needs of the IoT in mind can meet the challenges. What are some key features to seek out when evaluating MCUs? Your battery-powered IoT design will benefit from:
- Processing power for complex applications
- Low power consumption
- Energy-efficient wireless communication
- Robust security to protect your valuable IP and data
- Small packages
Maximum Performance at Minimal Power for the IoT
One of the newest devices in Maxim Integrated's DARWIN family of ultra-low-power Arm microcontrollers is well-suited to meet the challenges of wireless, battery-powered IoT devices. The MAX32666 is a dual-core Arm Cortex-M4 with floating-point unit MCU, featuring BLE 5.2 radio connectivity. The device addresses IoT system design challenges by providing:
- The combination of the dual-core processor that operates up to 96MHz with integrated BLE 5.2, large on-board memory, high I/O count, and fast peripherals to deliver the high performance needed. Having a dual core allows the flexibility of running the main application on one core and radio/sensor operation on the other.
- An integrated single-inductor, multiple-output (SIMO) regulator, which contributes to longer battery life.
- Very low active and standby power with selectable memory retention.
- Robust hardware security with a trust protection unit (TPU) and a secure bootloader to protect sensitive data.
- Added robustness with integrated error correcting code (ECC) on flash, SRAM, and cache memories to prevent bit flips.
- A small 3.8mm x 4.2mm WLP.
Compared to competitive solutions, the MAX32666 can help reduce bill of materials (BOM) costs by one-third. The DARWIN family of ultra-low-power MCUs provides a high level of integration and security along with a choice of memory size and cores. The devices are designed to extend battery life, store and process a large amount of data, resist security threats, and support the demands of the IoT.
To test-drive the MAX32666, check out the MAX32666EVKIT. There's also a rapid development platform, the MAX32666FTHR, that lets you quickly implement battery-optimized Bluetooth 5 solutions using the MCU. This board includes the MAX1555 1-cell Li+ battery charger for battery management, as well as a variety of peripherals in a 0.9in x 2.0in dual-row header footprint.