STM32WL: Dual-Core Sub-GHZ Wireless System-on-Chip (SoC) for Multi-protocol and Long-Range Communications

14 December 2020 - 0 Comments

STMicroelectronics has introduced the STM32WL long-range sub-GHZ wireless System on chip (SoC) family for providing flexible configurations and package options for diverse mass-market applications. The series combines ST’s STM32 ultra-low-power microcontroller (MCU) architecture with a sub-GHz radio subsystem that supports multiple modulation schemes. The SoC ICs were designed to connect devices to LoRa-based Low-Power Wide-Area Networks (LPWANs); hence the user can create Internet-of-Things (IoT) devices that are extremely compact, energy-efficient, and reliable.

The STM32WL supports both LoRa that allows high receiving sensitivity at low RF signal power and (G)FSK, (G)MSK, and BPSK modulation used by Sigfox and wireless Meter-Bus (wM-Bus) protocols. With the help of the selectable dual-power output, the customers can comply with RF-power restrictions for unlicensed frequency bands in all territories worldwide.

The STM32WL comes with the dual-core STM32WL55, based on an Arm Cortex-M4 core and a Cortex-M0+ MCU core. This dual-core architecture allows hardware isolation for enhancing cybersecurity and allows application updates without the need to re-certify the device as a new radio product. It also enhances the real-time performance of both the radio and application. The radio has been designed based on proven Semtech SX126x transceiver IP and contains two internal power amplifiers with 15dBm and 22dBm. The high-power and low-power transmitter modes cover the global unlicensed frequency range from 150MHz to 960MHz.

The high level of RF integration eliminates the need for an external power amplifier (PA) during single-crystal synchronization of the High-speed External (HSE) clock and radio. The 256Kbyte flash allows the developers to choose the optimal code and data storage density for the entire platform.

The device comes with various cybersecurity features such as hardware symmetric encryption and Public Key Accelerators, True Random Number Generator (TRNG), sector protection against read/write operation, dual-core secure areas isolation, and support for state-of-the-art cryptographic algorithms including RSA, ECC, and ECDSA.

Features of STM32WL

Core: 32-bit Arm Cortex-M4 CPU and 32-bit ArmCortex-M0+ CPU
Frequency range: 150 MHz to 960 MHz
Modulation: LoRa, (G)FSK, (G)MSK, and BPSK
Internal power amplifiers with 15dBm and 22dBm
256-Kbyte Flash memory and 64-Kbyte RAM
1.8 V to 3.6 V power supply
–40 °C to +105 °C temperature range

Note: More technical information can be found in the STM32WL55xx STM32WL54xx datasheet linked at the bottom of this page and on the STM32WL Microcontrollers product page.