The STM32L431xx devices are the ultra-low-power microcontrollers based on the high-performance Arm® Cortex®-M4 32-bit RISC core operating at a frequency of up to 80 MHz. The Cortex-M4 core features a Floating point unit (FPU) single precision which 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) which enhances application security.
The STM32L431xx devices embed high-speed memories (Flash memory up to 256 Kbyte, 64 Kbyte of SRAM), a Quad SPI flash memories interface (available on all packages) and an extensive range of enhanced I/Os and peripherals connected to two APB buses, two AHB buses and a 32-bit multi-AHB bus matrix.
The STM32L431xx devices embed several protection mechanisms for embedded Flash memory and SRAM: readout protection, write protection, proprietary code readout protection and Firewall.
The devices offer a fast 12-bit ADC (5 Msps), two comparators, one operational amplifier, two DAC channels, an internal voltage reference buffer, a low-power RTC, one general-purpose 32-bit timer, one 16-bit PWM timer dedicated to motor control, four general-purpose 16-bit timers, and two 16-bit low-power timers.
In addition, up to 21 capacitive sensing channels are available.
They also feature standard and advanced communication interfaces.
The STM32L431xx operates in the -40 to +85 °C (+105 °C junction), -40 to +105 °C (+125 °C junction) and -40 to +125 °C (+130 °C junction) temperature ranges from a 1.71 to 3.6 V power supply. A comprehensive set of power-saving modes allows the design of low-power applications.
Some independent power supplies are supported: analog independent supply input for ADC, DAC, OPAMP and comparators. A VBAT input allows to backup the RTC and backup registers.
The STM32L431xx family offers nine packages from 32 to 100-pin packages.
Feature
- 1.71 V to 3.6 V power supply
- -40 °C to 85/105/125 °C temperature range
- 200 nA in VBAT mode: supply for RTC and 32x32-bit backup registers
- 8 nA Shutdown mode (5 wakeup pins)
- 28 nA Standby mode (5 wakeup pins)
- 280 nA Standby mode with RTC
- 1.0 μA Stop 2 mode, 1.28 μA with RTC
- 84 μA/MHz run mode
- Batch acquisition mode (BAM)
- 4 μs wakeup from Stop mode
- Brown out reset (BOR)
- Interconnect matrix
- 1.25 DMIPS/MHz (Drystone 2.1)
- 273.55 CoreMark (3.42 CoreMark/MHz @ 80 MHz)
- 176.7 ULPBench score
- 4 to 48 MHz crystal oscillator
- 32 kHz crystal oscillator for RTC (LSE)
- Internal 16 MHz factory-trimmed RC (±1%)
- Internal low-power 32 kHz RC (±5%)
- Internal multispeed 100 kHz to 48 MHz oscillator, auto-trimmed by LSE (better than ±0.25 % accuracy)
- Internal 48 MHz with clock recovery
- 2 PLLs for system clock, audio, ADC
