STM32WL31C8V6 [STMicroelectronics]

The STM32WL31xx is a high performance ultra-low power wireless application processor, intended for RF wireless applications in the sub-1 GHz band. It is designed to operate in both the license-free ISM and SRD frequency bands such as 433, 868, and 915 MHz.

It adopts a single-core architecture embedding an Arm® 32-bit Cortex®-M0+ CPU that can operate up to 64 MHz. It integrates high-speed and flexible memory types: up to 128 Kbyte flash memory, and up to 16 Kbyte RAM, one-time programmable (OTP) memory area of 1 Kbyte.

The STM32WL31xx embeds a wide set of peripherals, including: a 12-bit, 8 channel ADC, RTC, IWDG, general purpose timers, AES-128, RNG, CRC, communication interfaces such as USART, SPI, and I2C. Moreover, the security features enable secure boot with USART/SWD block (write protection) and sensitive information storage in flash (read-out protection).

Direct data transfer between memory and peripherals and from memory-to-memory is supported by seven DMA channels with fully-flexible channel mapping by the DMAMUX peripheral.

It can be configured to support standalone or network processor applications. In the first configuration, the STM32WL31xx operates as single device in the application for managing both the application code and proprietary sub-1 GHz protocol stacks.

It operates in the -40 to +105 °C temperature range from a 1.7 V to 3.6 V power supply. A comprehensive set of power-saving modes enables the design of low-power applications.

The integrated highly efficient SMPS step-down converter together with the state transition speed between low-power and active states minimize in every condition the average current consumption enabling the STM32WL31xx to be the wireless application processor most suited for battery-operated applications.

The STM32WL31xx comes in different package versions supporting up to 32 I/Os for the VFQFPN48 package and 17 I/Os for the VFQFPN32 package.

• Includes ST state-of-the-art patented technology
• Ultra-low power sub-1GHz wireless system-on-chip
• Programmable MCU
  • Core: Arm^® Cortex^®-M0+ 32-bit, running up to 64 MHz
  • Program memory: 64-Kbyte / 128-Kbyte flash memory
  • Data memory: 8-Kbyte / 16-Kbyte SRAM (full retention)
  • Additional storage: 1-Kbyte OTP (user data)
• Radio
  • Frequency bands: 413-479 MHz, 826-958 MHz
  • Air data rate from 0.1 to 600 kbit/s
  • Programmable TX power up to +20dBm
  • RX sensitivity @ 1% BER:
    • -132 dBm @300 bit/s 433 MHz OOK
    • -128 dBm @300 bit/s 868 MHz 2(G)FSK
    • -112 dBm @38.4 bit/s 868 MHz 2(G)FSK
  • Modulation schemes:
    • 2(G)FSK, 2(G)MSK, 4(G)FSK
    • OOK, ASK
    • D-BPSK
    • DSSS (direct sequence spread spectrum)
    • I/Q channels data access
    • Compatible with proprietary and standardized wireless protocols (W-MBUS, Sigfox, Mioty, KNX-RF, IEEE 802.15.4g, others)
  • Suitable for worldwide certifications:
    • Europe: ETSI EN 300 220, category 1 compliant, ETSI EN 303 131
    • US: FCC part 15 and part 90
    • Japan: ARIB STD T67, T108
  • Fully-configurable hardware sequencer for autonomous radio operations (Sniff mode, Frequency hopping, Low Duty Cycle mode, Listen before talk)
• Ultra-low power architecture
  • Dynamic current consumption: 21 µA/MHz
  • 14 nA in Shutdown mode
  • 960 nA in Deepstop mode
  • Radio only consumption:
    • 4 mA in RX
    • 8 mA in TX @ +10 dBm
    • 78 mA in TX @ +20 dBm
  • Consumption: 1.3 mA current in WFI conditions (direct HSE mode)
  • Wakeup capability from both Deepstop and Shutdown modes
• Peripherals and analog front-end
  • 12-bit ADC: up to 1 Msample/s with 8 single ended channels (or 4 differentials)
  • Temperature monitoring
• Communication interfaces
  • Up to 32 GPIOs (VFQFPN48), all with retention capabilityUp to 17 GPIOs (VFQFPN32), all with retention capability
  • 1x USART. Supports of LIN, Smartcard Protocol, IrDA, SIR ENDEC specifications, and modem operations (CTS/RTS)
  • 1x LPUART (available also in low-power mode), with wakeup capability
  • 1x SPI
  • 1x SPI with I2S interface multiplexed
  • I2C (SMBus/PMBus)
  • 1x DMA 8 channels controller, supporting ADC, SPIs, I2Cs, USART, LPUART, timers, AES
• Clock sources and timers
  • Flexible clocking scheme, featuring:
    • 64 MHz (HSI or PLL)
    • Fail-safe 48 MHz crystal oscillator (HSE), with integrated trimming capacitors
    • 32 kHz crystal oscillator (LSE)
    • Integrated low-power 32 kHz RC (LSI)
  • 1x 16-bits, four channels general purpose timer
  • 1x 16-bits, two channels general purpose timer
  • 1x RTC
  • 1x independent watchdog
  • Radio timer with wakeup capability
• Security
  • Secure bootloader with SWD disabling
  • AES-128 co-processor and 16-bit TRNG
  • Embedded UART bootloader with selectable write and read-out protection
• Operating range and reset
  • Ultra-low-power power-on-reset (POR) and power-down-reset (PDR)
  • Programmable voltage detector (PVD)
  • Supply voltage: from 1.7 to 3.6 V
  • Temperature range: -40 ºC to 105 ºC
• All packages are ECOPACK2 compliant