STMicroelectronics has announced the general availability of its STM32WL33 wireless microcontrollers (MCUs), offering advanced features that simplify IoT product design, reduce time to market, and extend battery life. These devices, which integrate ST’s next-generation sub-GHz long-range radio and an Arm® Cortex®-M0+ core, are tailored for applications in smart metering, industrial automation, asset tracking, and environmental monitoring.
A Revolution in IoT Wireless Solutions
The STM32WL33 MCUs are designed to power the future of IoT with flexible options and ultra-low-power architecture. They cater to diverse use cases, from smart cities to agriculture and logistics. Applications include soil condition reporting, animal welfare monitoring, forest-fire detection, water metering, and leakage detection.
Notable features include a unique analog flow-sensor controller (LCSC), which streamlines water metering by measuring fluid flow without requiring MCU intervention. This integration not only optimizes cost and design but also enhances battery life to over 15 years while incorporating anti-tampering capabilities.
For further power savings, the MCU includes a wideband radio that listens for wake-up signals while the main communication radio is off. This functionality is particularly beneficial for drive-by metering devices or firmware upgrade scenarios, enabling efficient, always-on operation without significant battery drain.
Flexible and Powerful Design Features
The STM32WL33 offers a robust set of integrated components, including:
- 256KB Flash Memory and 32KB SRAM
- A 16-segment LCD driver
- A 12-bit, 1Msample/s ADC
- Analog comparator, DAC, multiple timers, and a real-time clock (RTC)
For enhanced security, the MCUs provide features such as secure boot, secure firmware updates, 128-bit AES encryption, and a random-number generator (RNG).
These MCUs operate in license-free frequency bands (413-479 MHz, 826-958 MHz), with a special variant supporting 169 MHz. Two programmable power amplifiers allow selectable RF output power of +14dBm or +20dBm, making the devices suitable for global deployment and roaming applications.
Advanced Radio Performance
The configurable radio offers multi-protocol support and modulation flexibility, including 4-(G)FSK, 2-(G)FSK, DSSS, and ASK. The integrated Radio Sequencer automates common operations like frequency-hopping and low-duty-cycle transmissions, reducing MCU workload and boosting efficiency.
With a receive sensitivity of -132dBm at 300bps (433MHz OOK), the radio ensures reliable long-range communication, supporting wireless links of over 1 km at +20dBm output power.
An IQ interface enables custom modulation schemes and enhanced sensitivity, allowing users to develop and optimize their proprietary protocols using tools like GNURadio. Standard protocols such as wM-Bus, Sigfox, Wi-SUN, and 6LoWPAN are also supported.
Comprehensive Development Ecosystem
STMicroelectronics provides a rich ecosystem to support the STM32WL33 series, including:
- STM32CubeWL3 Software and Middleware
- NUCLEO-WL33CC1 and NUCLEO-WL33CC2 Boards
- Matched Filters and Reference Designs for Simplified RF Development
The Wireless Studio Environment (STM32CubeWiSE) accelerates development with intuitive graphical tools for RF protocol automation, testing, and certification.
Availability and Pricing
The STM32WL33 MCUs are now available, with prices starting at $2.03 for the STM32WL33K8V6 in a QFN32 package (10,000-unit orders). NUCLEO boards for development are priced at $50.00 and can be purchased from ST distributors or the eSTore.
For more information, visit STMicroelectronics’ website.
