Ultra-low-power dual core Arm Cortex-M4 MCU 64 MHz, Cortex-M0 32MHz with 1 Mbyte Flash, BLE, 802.15.4, USB, LCD, AES-256

The STM32WB55xx multiprotocol wireless and ultra-low-power devices embed a powerful and ultra-low-power radio compliant with the Bluetooth® Low Energy SIG specification v5.0 and with IEEE 802.15.4-2011. They contain a dedicated Arm® Cortex® -M0+ for performing all the real-time low layer operation.

The STM32WB55xx devices are designed to be extremely low-power and are based on the high-performance Arm® Cortex®-M4 32-bit RISC core operating at a frequency of up to 64 MHz. The Cortex®-M4 core features a Floating point unit (FPU) single precision that supports all Arm® single-precision data-processing instructions and data types. It also implements a full set of DSP instructions and a memory protection unit (MPU) that enhances application security.

Enhanced inter-processor communication is provided by the IPCC with six bidirectional channels. The HSEM provides hardware semaphores used to share common resources between the two processors.

The STM32WB55xx devices embed high-speed memories (Flash memory up to 1 Mbyte, up to 256 Kbyte of SRAM), a Quad-SPI Flash memory interface (available on all packages) and an extensive range of enhanced I/Os and peripherals.

Direct data transfer between memory and peripherals and from memory to memory is supported by 14 DMA channels with a full flexible channel mapping by the DMAMUX peripheral.

The STM32WB55xx devices embed several mechanisms for embedded Flash memory and SRAM: readout protection, write protection and proprietary code readout protection. Portions of the memory can be secured for Cortex® -M0+ exclusive access.

The two AES encryption engines, PKA and RNG enable lower layer MAC and upper layer cryptography. A customer key storage feature may be used to keep the keys hidden.

The devices offer one fast 16-bit ADC and two ultra-low-power comparators associated with a high accuracy reference voltage generator

The STM32WB55xx devices embed a low-power RTC, one advanced 16-bit timer, one general-purpose 32-bit timer, two general-purpose 16-bit timers, and two 16-bit low-power timers.

In addition, up to 28 capacitive sensing channels are available. The devices also embed an integrated LCD driver up to 8x40 or 4x44, with internal step-up converter.

They also feature standard and advanced communication interfaces:

The STM32WB55xx operate in the -40 to +105 °C (+125 °C junction) temperature range from a 1.71 to 3.6 V power supply. A comprehensive set of power-saving modes enables the design of low-power applications.

The STM32WB55xx integrate a high efficiency SMPS step-down converter. It includes independent power supplies for analog input for ADC and comparators, as well as a 3.3 V dedicated supply input for USB.

A VBAT dedicated supply allows the devices to back up the LSE 32.768KHz oscillator, the RTC and the backup registers, thus enabling the STM32WB55xx to supply these functions even if the main VDD is not present through a CR2032-like battery, a Supercap or a small rechargeable battery.

The STM32WB55xx family offers three packages, from 48 to 100 pins.

Key Features

  • Includes ST state-of-the-art patented technology
  • Radio
    • 2.4 GHz RF transceiver supporting Bluetooth® specification v5.0 and IEEE 802.15.4-2011 PHY and MAC
    • RX Sensitivity: -96 dBm (Bluetooth® Low Energy at 1 Mbps), -100 dBm (802.15.4)
    • Programmable output power up to +6 dBm with 1 dB steps
    • Integrated balun to reduce BOM
    • Support for 2 Mbps
    • Dedicated Arm® 32-bit Cortex® M0 + CPU for real-time Radio layer
    • Accurate RSSI to enable power control
    • Compliant with radio frequency regulations ETSI EN 300 328, EN 300 440, FCC CFR47 Part 15 and ARIB STD-T66
  • Ultra-low-power platform
    • 1.71 V to 3.6 V power supply
    • – 40 °C to 85 / 105 °C temperature ranges
    • 30 nA shutdown mode
    • 600 nA Standby mode + RTC + 32 KB RAM
    • 1.8 μA Stop mode + RTC + 256 KB RAM
    • Active-mode MCU + RF (SMPS ON): < 50 μA/MHz
    • RX: 3.8 mA
    • TX at 0 dBm: 5.5 mA
  • Core: Arm® 32-bit Cortex®-M4 CPU with FPU, Adaptive real-time accelerator (ART Accelerator™) allowing 0-wait-state execution from Flash memory, frequency up to 64 MHz, MPU, 80 DMIPS and DSP instructions
  • Supply and Reset management
    • High efficiency embedded SMPS step-down converter
    • Ultra-safe, low-power BOR (brownout reset) with five selectable thresholds
    • Ultra-low-power POR/PDR
    • Programmable voltage detector (PVD)
    • VBAT mode with RTC and backup registers
  • Clock sources
    • 32 MHz crystal oscillator with integrated trimming capacitors (Radio and CPU clock)
    • 32 kHz crystal oscillator for RTC (LSE)
    • Internal low-power 32 kHz (±5%) RC (LSI1)
    • Internal low-power 32 kHz (stability ±500 ppm) RC (LSI2)
    • Internal multispeed 100 kHz to 48 MHz oscillator, auto-trimmed by LSE (better than ±0.25 % accuracy)
    • High Speed internal 16 MHz factory trimmed RC (±1%)
    • 2x PLL for system clock, USB, SAI and ADC
  • Memories
    • Up to 1 MB Flash with sector protection (PCROP) against R/W operations, enabling authentic Bluetooth® Low Energy and 802.15.4 SW stack
    • Up to 256 KB RAM, including 64 KB with hardware parity check
    • 20x32-bit Backup Register
    • Boot loader supporting, USART, SPI, I2C and USB interfaces
    • OTA (Over the Air) Bluetooth® Low Energy and 802.15.4 update
    • Quad SPI memory interface with XIP
  • Rich Analog peripherals (down to 1.62 V)
    • 12-bit ADC 4.26Msps, up to 16-bit with hardware oversampling, 200 μA/Msps
    • 2x ultra-low-power comparator
    • Accurate 2.5 V or 2.048 V reference voltage buffered output
  • System peripherals
    • Inter Processor Communication Controller (IPCC) for communication with Bluetooth® Low Energy and 802.15.4
    • HW semaphores for resources sharing between CPUs
    • 2x DMA controllers (7x channels each) supporting ADC, SPI, I2C, USART, QSPI, SAI, AES, Timers
    • 1x USART (ISO 7816, IrDA, SPI Master, Modbus and Smartcard mode)
    • 1x LPUART (Low Power)
    • 2x SPI 32 Mbit/s
    • 2x I2C (SMBus/PMBus)
    • 1x SAI (dual channels)
    • 1x USB 2.0 FS device, crystal-less, BCD and LPM
    • Touch Sensing controller, up to 28 channels
    • LCD 8x40 with step-up converter
    • 1x 16-bit, four channels advanced timer
    • 2x 16-bits, two channels timer
    • 1x 32-bits, four channels timer
    • 2x 16-bits ultra-low-power timer
    • 1x independent Systick
    • 1x independent watchdog
    • 1x window watchdog
  • Security & ID
    • Secure Firmware Installation (SFI) for Bluetooth® Low Energy and 802.15.4 SW stack
    • Hardware Encryption AES 256-bit
    • Customer key storage / key manager services
    • HW Public Key Authority (PKA)
    • Cryptographic algorithms: RSA, Diffie-Helman, ECC over GF(p)
    • True random number generator (TRNG)
    • Sector protection against R/W operation (PCROP)
    • CRC calculation unit
    • 96-bit unique ID
    • 64-bit unique ID. Possibility to derive 802.15.5 64-bit and Bluetooth® Low Energy 48-bit EUI
  • Up to 72 fast I/Os, 70 of them 5 V-tolerant
  • Development support
    • Serial wire debug (SWD), JTAG for the Application processor
    • Application cross trigger with input and output
    • Embedded Trace Macrocell™ for application
  • All packages are ECOPACK2® compliant

Circuit Diagram


Technical Documentation

Product Specifications
Description Version Size
DB2885 DB2885: Multiprotocol wireless 32-bit MCU Arm®-based Cortex®-M4 with FPU, Bluetooth® Low Energy and 802.15.4 radio solution 2.0 216 KB
Application Notes
Description Version Size
AN1709 AN1709: EMC design guide for ST microcontrollers 2.0 843 KB
AN1181 AN1181: Electrostatic discharge sensitivity measurement 1.6 49 KB
AN4750 AN4750: Handling of soft errors in STM32 applications 2.1 410 KB
AN4803 AN4803: High-speed SI simulations using IBIS and board-level simulations using HyperLynx SI on STM32 32-bit ARM® Cortex® MCUs 1.1 2 MB
AN2834 AN2834: How to get the best ADC accuracy in STM32 microcontrollers 3.1 1 MB
AN4229 AN4229: How to implement a vocoder solution using STM32 microcontrollers 1.1 466 KB
AN2867 AN2867: Oscillator design guide for STM8AF/AL/S and STM32 microcontrollers 11.0 2 MB
AN4655 AN4655: Virtually increasing the number of serial communication peripherals in STM32 applications 1.1 338 KB
Technical Notes & Articles
Description Version Size
TN1163 TN1163: Description of WLCSP for microcontrollers and recommendations for its use 4.0 1 MB
TN0830 TN0830: How to use EWARM 6.2x with projects built with EWARM 6.1 and previous versions 1.2 97 KB
TN1204 TN1204: Tape and reel shipping media for STM32 microcontrollers in BGA packages 2.1 745 KB
TN1205 TN1205: Tape and reel shipping media for STM8 and STM32 microcontrollers in FPN packages 3.0 753 KB
TN1206 TN1206: Tape and reel shipping media for STM8 and STM32 microcontrollers in QFP packages 3.0 830 KB
TN1207 TN1207: Tape and reel shipping media for STM8 and STM32 microcontrollers in SO packages 1.0 755 KB
TN1208 TN1208: Tape and reel shipping media for STM8 and STM32 microcontrollers in TSSOP and SSOP packages 1.0 743 KB

Presentations & Training Material

Description Version Size
New STM32WB Series MCU with built-in BLE 5 and IEEE 802.15.4 1.0 1 MB
STM32 Development Boards Portfolio 1.0 3 MB

Publications and Collaterals

Description Version Size
Get ready for the largest IoT development ecosystem 18.02 748 KB
STM32 Nucleo boards - Unified scalable offering 17.11 1 MB
STM32WB Wireless Series with BLE 5.0 & IEEE 802.15.4 18.02 432 KB
Description Version Size
STM32 32-bit MCU family - Leading supplier of Arm® Cortex®-M microcontrollers 18.02 2 MB

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Sample & Buy

Part Number Package Packing Type Operating Temperature (°C) (min) Operating Temperature (°C) (max) Marketing Status Unit Price (US$) * Quantity ECCN (EU) ECCN (US) Country of Origin More info Order from ST Order from Distributors
STM32WB55CGU7 UFQFPN 48 7x7x0.55 Tray -40 105 Preview - 10000 5A002A4 5A002A4 - MORE INFO No availability reported, please contact our Sales office
STM32WB55CGU6 UFQFPN 48 7x7x0.55 Tray -40 85 Preview - 10000 5A002A4 5A002A4 - MORE INFO No availability reported, please contact our Sales office

(*) Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office  or our Distributors

Quality & Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
STM32WB55CGU7 PreviewUFQFPN 48 7x7x0.55IndustrialEcopack2
STM32WB55CGU6 PreviewUFQFPN 48 7x7x0.55IndustrialEcopack2

(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.