STMicroelectronics releases long-range wireless microcontrollers for energy-efficient connectivity in smart metering, smart building, and industrial monitoring

New STM32 system-on-chip with low power and multi-protocol support simplifies wireless system design for diverse use cases

Especially valuable in remotely deployed applications including metering and monitoring devices and data from alarm systems, actuators, and sensors in today’s smart buildings, smart factories, and smart cities, the STM32WL3 wireless MCUs can help limit power consumption and prioritize activities. Adoption and use of these efficient MCUs can lead to improved user experience, service delivery, and reduced environmental footprint. Device and application designers can leverage ST’s wireless MCUs to develop and deliver new products to the world quickly for maximum benefit.

The latest innovation in ST’s lineup of integrated wireless chips, the STM32WL3 contains an advanced, power-efficient multi-protocol radio suitable for long-range communication using license-free frequency bands reserved globally for industrial, scientific, and medical (ISM) applications. In addition to the main radio, ST has integrated an industry-unique ultra-low-power radio the system can power-down to save energy while listening continuously for a wake-up signal.

Lead customers are using STM32WL3 MCUs to add value to smart connected devices. For example, Lierda Internet of Things Technology, is using the STM32WL33 to reduce power and add long range wireless connectivity to existing networking products. Leveraging the MCU’s wake-up radio to minimize power consumption, the Lierda module monitors and maintains network equipment across a point-to-point or point-to-multipoint wireless connection.

Another customer, Silent Smart Technology, has created a family of modules based on STM32WL3 wireless MCUs that operate in various sub-1GHz frequency bands. The modules support multiple transmission modes, channel monitoring, wireless relay, and other functions. The MCU’s wakeup feature allows the modules to operate in deep-sleep mode, consuming only about 1µA overall current while remaining ready to return to full operation.

“ST’s new highly featured, long-range STM32WL3 wireless microcontrollers help customers like Lierda and Silent Smart create innovative and flexible products, achieving very low power and fast time to market,” said Benoit Rodriguez, Wireless Business Line General Manager, STMicroelectronics. “Special features such as the wake-up radio and our flow-metering LC sensor controller enable energy-saving designs in smart metering, smart agriculture, and asset tracking that run for up to 15 years from a small battery.”

The STM32WL3 joins ST’s growing family of devices that combine the radio with the main application controller to ease engineering challenges, reduce power and size, and enhance reliability.

Further technical information:

• The long-range radio on the STM32WL3 MCUs operates in the internationally designated license-free frequency bands, 413MHz – 479MHz and 826MHz – 958MHz, with the support for 169MHz coming in 2024.
• The radio is multi-protocol and multi-modulation capable, supporting 4-(G)FSK up to 600kbit/s, 2-(G)FSK, (G)MSK, DBPSK, DSSS, OOK, ASK modulation schemes to maximize versatility and ease deployment.
• On-board peripherals include an LCD driver, a 12-bit 1Msample/s ADC, analog comparator, DAC, and multiple timers. Together with an integrated balun, RF power amplifier, and SMPS, they minimize external BoM for a cost-optimized solution with short time-to-market.

The complete lineup contains devices with Flash density from 64KB to 256KB and 16KB or 32KB RAM, in a 32-pin or 48-pin VFQFPN package. There is also an extended temperature range option, from -40°C to 105°C. All variants are covered with ST’s 10-year longevity guarantee for industrial products. Sample quantities are available now.

Tailored to the specific needs of smart-metering applications, the STM32WL3 embeds an LCD controller and a specific peripheral — LC sensor controller – for fluid flow measurement that eases the design of water meters and heat-cost allocators. Multi-protocol support enables cost-efficient deployment of one single platform over different long-range wireless technologies, including Sigfox, KNX, mioty, M-Bus, and others.

Prices start from $2.04 for orders of 10,000 pieces. For larger quantity pricing, please contact your ST sales office. Evaluation kits will be available shortly.

Ultra-low power multi-modulation wireless STM32WL3x microcontrollers

Based on Arm Cortex-M0+ core, sub-GHz radio, and wideband wake-up radio, STM32WL3x microcontrollers support multiple modulations and an IQ interface for custom modulations for even more flexibility.

The STM32WL3 is a highly integrated long-range wireless solution for IoT devices offering a simplified design approach and low power consumption for extended battery life.

It offers the essential features for wireless IoT devices, including:
• Contributes to longer battery life: Extends battery life by reducing the power consumption of wireless applications (low power features). Enables 10 years battery life in many applications and the use of energy harvesting.
• Sub-GHz radio provides full flexibility: Multiple modulations and protocols. Reduces the R&D development effort by using one single platform to support many communication protocols (excluding LoRa).
• Reduces design complexity: Optimizes the bill of materials (BOM), reducing the end device footprint and design complexity.

Product types:

STM32WL3 provides a dual radio architecture extending the battery life of IoT applications.

• Ultra-low power Sub-1GHz RX/TX transceiver

The main radio features state-of-the-art low power consumption with a Tx current down to 9 mA at 10 dBm.
Available modulations and an IQ interface can also be used in legacy and proprietary protocols.

The radio is suitable for systems targeting compliance with radio regulations including but not limited to Europe (ETSI EN 300-220), USA (FCC part 15 and part 90) and the Japan ARIB STD T67, T-108. Frequency coverage from 413-479 MHz and 826-958 MHz supports major sub-GHz ISM bands around the world such as Europe, Asia Pacific, and the Americas.

• Wake-up radio receiver

The STM32WL3 provides a secondary radio featuring a low power autonomous wake up receiver and achieving down 4 μA current consumption in always on mode.

For greater flexibility, it supports wide frequency bands from 100 MHz – 2.4 GHz.

The STM32WL3x line includes a wide variety of communication features including up to 32 GPIOs. It integrates sensing peripherals, for measurement of fluid flow metering, and an internal LCD segment driver. It is based on a low-power architecture for power consumption optimization, multiple low-power modes to maximize battery life.

The STM32WL3x MCUs also include embedded security hardware functions such as 128 AES hardware encryption and 16-bit TRNG.

Discover our portfolio

STM32WL3 microcontrollers provide designers with flexibility in terms of memory size and pin counts.

Two ECOPACK2^® compliant packages are available to address different levels of complexity to ensure a cost-efficient fit for application requirements.