Overview
The STM32L431KBU6TR is an ultra-low-power microcontroller from STMicroelectronics, part of the STM32L431xx family. It is 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 includes a Floating Point Unit (FPU) for single-precision data processing, DSP instructions, and a Memory Protection Unit (MPU) for enhanced application security.
This microcontroller is designed for low-power applications, featuring a comprehensive set of power-saving modes and a wide operating temperature range from -40 °C to +85 °C, +105 °C, or +125 °C. It supports various independent power supplies, including an analog independent supply input for ADC, DAC, OPAMP, and comparators, and a VBAT input for backing up the RTC and backup registers.
Key Specifications
| Specification | Details |
|---|---|
| Core | Arm® 32-bit Cortex®-M4 CPU with FPU, up to 80 MHz |
| Flash Memory | Up to 256 KB single bank Flash |
| SRAM | 64 KB, including 16 KB with hardware parity check |
| Power Supply | 1.71 V to 3.6 V |
| Temperature Range | -40 °C to +85 °C, +105 °C, or +125 °C |
| Power Consumption | 200 nA in VBAT mode, 8 nA Shutdown mode, 28 nA Standby mode, 280 nA Standby mode with RTC, 1.0 µA Stop 2 mode, 1.28 µA with RTC |
| ADC | 1x 12-bit ADC, 5 Msps, up to 16-bit with hardware oversampling |
| DAC | 2x 12-bit DAC output channels, low-power sample and hold |
| Timers | 1x 16-bit advanced motor-control, 1x 32-bit, 2x 16-bit general purpose, 2x 16-bit basic, 2x low-power 16-bit timers |
| Communication Interfaces | 1x SAI, 3x I2C FM+, 4x USARTs, 1x LPUART, 3x SPIs (and 1x Quad SPI), CAN (2.0B Active), SDMMC interface |
| Capacitive Sensing Channels | Up to 21 channels, supporting touchkey, linear, and rotary touch sensors |
| Package | UFQFPN 32 5x5x0.55 mm |
Key Features
- Ultra-low-power with FlexPowerControl
- Arm® 32-bit Cortex®-M4 CPU with FPU, Adaptive real-time accelerator (ART Accelerator™), frequency up to 80 MHz, MPU, 100DMIPS, and DSP instructions
- Comprehensive set of power-saving modes: VBAT mode, Shutdown mode, Standby mode, Stop 2 mode
- Batch acquisition mode (BAM) and 4 µs wakeup from Stop mode
- Brown out reset (BOR) and interconnect matrix
- RTC with HW calendar, alarms, and calibration
- Rich analog peripherals: 12-bit ADC, 12-bit DAC, operational amplifier, ultra-low-power comparators
- Multiple communication interfaces: SAI, I2C, USARTs, LPUART, SPIs, CAN (2.0B Active), SDMMC
- Up to 21 capacitive sensing channels
- 14-channel DMA controller, true random number generator, CRC calculation unit, 96-bit unique ID
- Development support: serial wire debug (SWD), JTAG, Embedded Trace Macrocell™
- All packages are ECOPACK2® compliant
Applications
The STM32L431KBU6TR is suitable for a wide range of applications requiring low power consumption and high performance. These include:
- Industrial automation and control systems
- Personal electronics such as wearables and smart home devices
- Medical devices requiring precise analog and digital capabilities
- Automotive systems, especially those needing advanced motor control and communication interfaces
- IoT devices that demand low power and robust communication features
Q & A
- What is the core architecture of the STM32L431KBU6TR?
The STM32L431KBU6TR is based on the Arm® 32-bit Cortex®-M4 CPU with a Floating Point Unit (FPU), operating at up to 80 MHz.
- What are the power supply and temperature ranges for this microcontroller?
The power supply range is 1.71 V to 3.6 V, and the operating temperature range is -40 °C to +85 °C, +105 °C, or +125 °C.
- What are the key power-saving modes available?
The key power-saving modes include VBAT mode, Shutdown mode, Standby mode, and Stop 2 mode.
- What analog peripherals are available on this microcontroller?
The microcontroller features a 12-bit ADC, 12-bit DAC, an operational amplifier, and ultra-low-power comparators.
- What communication interfaces does the STM32L431KBU6TR support?
It supports SAI, I2C, USARTs, LPUART, SPIs, CAN (2.0B Active), and SDMMC interfaces.
- How many capacitive sensing channels are available?
Up to 21 capacitive sensing channels are available, supporting touchkey, linear, and rotary touch sensors.
- What development tools and interfaces are supported?
The microcontroller supports serial wire debug (SWD), JTAG, and Embedded Trace Macrocell™.
- Is the package environmentally friendly?
- What is the typical current consumption in different modes?
The current consumption varies: 200 nA in VBAT mode, 8 nA in Shutdown mode, 28 nA in Standby mode, 280 nA in Standby mode with RTC, 1.0 µA in Stop 2 mode, and 1.28 µA with RTC.
- What is the purpose of the VBAT input?
The VBAT input is used to backup the RTC and backup registers.
