STMicroelectronics STM32WL55CCU6

Overview

STM32WL55CCU6 from STMicroelectronics is a dual-core 32-bit Arm® Cortex®-M4/M0+ SoC integrating sub-GHz radio (LoRa®, (G)FSK, (G)MSK, BPSK), 256 KB flash, 64 KB SRAM, hardware AES-256 and PKA, operating from 1.8–3.6 V across –40 °C to +105 °C. It enables secure, ultra-low-power LPWAN node design for battery-operated sensor networks and industrial telemetry.

For engineers reviewing the STM32WL55CCU6 datasheet, STM32WL55CCU6 pinout, STM32WL55CCU6 application, or STM32WL55CCU6 equivalent, key selection considerations include dual-core real-time partitioning, integrated RF transceiver performance (–148 dBm LoRa® RX sensitivity, +22 dBm TX), ultra-low-power modes (31 nA shutdown), and hardware security services (AES, RNG, PKA, SFU).

Technical Context

The device implements tightly coupled dual-CPU architecture: Cortex-M4 (48 MHz, ART Accelerator, DSP/MPU) handles application and protocol stack, while Cortex-M0+ (48 MHz, MPU) manages radio firmware and low-level timing-critical RF operations. Inter-processor communication uses IPCC mailboxes and HSEM semaphores.

Sub-GHz radio subsystem includes RF-PLL with programmable IF, configurable TX/RX paths supporting LoRa® spreading factors 7–12, FSK/GFSK data rates up to 300 kbps, and compliance with ETSI EN 300 220, FCC Part 15/90, and ARIB STD-T30/T-67. Integrated SMPS supports efficient power delivery across voltage scaling states.

Key Specifications

Pinout & Package

STM32WL55CCU6 is housed in a 48-pin UFQFPN package (7 × 7 mm, 0.5 mm pitch), optimized for compact LPWAN module integration and RF layout control. Pin assignments support dedicated RFIO, VDDRF, VSSRF, and matching network connections per ST reference designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar sub-GHz wireless MCU applications.

Compared with STM32WL55CCU6, STM32WL54CCU6 offers identical RF performance and security at lower memory cost, while CC1352P7RGZR adds 2.4 GHz capability but requires external secure element for comparable firmware integrity assurance.

Availability

STM32WL55CCU6 is available at Aetrix Electronics and suitable for smart utility metering, industrial predictive maintenance, asset tracking, and environmental monitoring requiring stable component supply and long-term lifecycle support.

Supply support for STM32WL55CCU6 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power ICs, sensors, and automotive-grade components since 1987.

The STM32WL series targets secure, ultra-low-power LPWAN endpoints, combining Arm dual-core processing with certified sub-GHz radio and hardware security to accelerate development of compliant IoT edge devices.

FAQ

What RF certifications does STM32WL55CCU6 support out-of-the-box?

STM32WL55CCU6's integrated radio complies with ETSI EN 300 220 (Europe), FCC CFR 47 Parts 15/90 (USA), and ARIB STD-T30/T-67 (Japan) when used with ST-recommended IPD matching networks and reference layouts. Certification-ready design files and test reports are provided in ST's AN5573 and UM2712 application notes.

How is dual-core firmware isolation enforced in STM32WL55CCU6?

Firmware isolation is enforced via hardware memory protection units (MPUs) on both Cortex-M4 and Cortex-M0+ cores, coupled with Global TrustZone Controller (GTZC) region-based access control. Secure boot validates M4 firmware first, then loads M0+ image into protected SRAM; inter-core IPC uses HSEM-locked mailboxes with configurable privilege levels.

Can STM32WL55CCU6 operate without an external crystal?

Yes - the device supports internal RC oscillators (16 MHz HSI, 32 kHz LSI) for basic operation, but LoRa® and (G)FSK modulation require the 32 MHz external crystal for precise symbol timing and frequency accuracy. TCXO support allows programmable supply voltage for enhanced stability in wide-temperature deployments.

What is the maximum achievable data rate in FSK mode?

In (G)FSK mode, STM32WL55CCU6 achieves up to 300 kbps raw data rate with 250 kHz RX bandwidth and 500 kHz TX deviation. Actual usable throughput depends on packet overhead, coding rate, and regulatory channel spacing - e.g., 50 kbps net payload is typical for ETSI-compliant 12.5 kHz channel operation.