STMicroelectronics STM32L4 32-Bit Low-Power Microcontrollers +FPU

STMicroelectronics STM32L4 32-Bit Low-Power Microcontrollers +FPU are ultralow-power MCUs based on the high-performance Arm® Cortex®-M4 32-bit RISC core operating at a frequency of up to 80MHz. 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 STM32L4 microcontroller is based on a new ultralow-power platform featuring FlexPowerControl. It extends flexibility to reach optimized power consumption. The STM32L4 outperforms the market in the ultra-low-power domain with an EEMBC ULPBench score of 150 ULPBench™-CP.

It offers up to 2Mbyte of Flash (dual bank) and up to 640Kbytes of SRAM. It delivers 100DMIPS/273 CoreMark thanks to the ST ART Accelerator™ at 80MHz. The entire system performance is optimized using a multi-AHB bus matrix and DMA controllers.

The STM32L4 microcontroller can be used to replace a current design using the STM32F4 to get low-power functionality. It has pin-to-pin compatibility and can replace the STM32F4 without changing the board layout.

Features

STM32L4x1, STM32L4x2, STM32L4x3
Ultralow-power with FlexPowerControl
- 1.71V to 3.6V power supply
- -40°C to 85/105/125°C temperature range
- 200nA in VBAT mode: supply for RTC and 32x32-bit backup registers
- 8nA Shutdown mode (5 wakeup pins)
- 28nA Standby mode (5 wakeup pins)
- 280nA Standby mode with RTC
- 1.0μA Stop 2 mode, 1.28μA Stop 2 with RTC
- 84μA/MHz run mode
- Batch acquisition mode (BAM)
- 4μs wakeup from Stop mode
- Brown out reset (BOR) in all modes except shutdown
- Interconnect matrix
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 80MHz, MPU, 100DMIPS/1.25DMIPS/MHz (Dhrystone 2.1), and DSP instructions
Clock Sources
- 4 to 48MHz crystal oscillator
- 32kHz crystal oscillator for RTC (LSE)
- Internal 16MHz factory-trimmed RC (±1%)
- Internal low-power 32kHz RC (±5%)
- Internal multispeed 100kHz to 48MHz oscillator, auto-trimmed by LSE (better than ±0.25 % accuracy)
- Internal 48MHz with clock recovery
- 2 PLLs for system clock, USB, audio, ADC
Performance Benchmark
- 1.25 DMIPS/MHz (Drystone 2.1)
- 273.55 Coremark® (3.42 Coremark/MHz @ 80MHz)
Energy Benchmark
- 176.7 ULPBench® score
Memories
- Up to 256KB single bank Flash, proprietary code readout protection
- 64KB of SRAM including 16KB with hardware parity check
- Quad SPI memory interface
Rich analog peripherals (independent supply)
- 1x12-bit ADC 5Msps, up to 16-bit with hardware oversampling, 200μA/Msps
- 2x12-bit DAC, low-power sample and hold
- 1x operational amplifier with built-in PGA
- 2x ultralow-power comparators
14-channel DMA controller
True random number generator
CRC calculation unit, 96-bit unique ID
AES: 128/256-bit key encryption hardware accelerator
Development support: serial wire debug (SWD), JTAG, Embedded Trace Macrocell™
RTC with HW calendar, alarms and calibration
LCD 8×40 or 4×44 with step-up converter
Up to 21 capacitive sensing channels: support touchkey, linear and rotary touch sensors
11x timers: 1x 16-bit advanced motor-control, 1x 32-bit and 2x 16-bit general purpose, 2x 16- bit basic, 2x low-power 16-bit timers (available in Stop mode), 2x watchdogs, SysTick timer
Up to 83 fast I/Os, most 5V-tolerant

STM32L4x5, STM32L4x6, STM32L4x7, STML4x9
Ultra-low-power with FlexPowerControl
- 1.71V to 3.6V power supply
- -40°C to 85/105/125°C temperature range
- 300nA in VBAT mode: supply for RTC and 32x32-bit backup registers (4nA without RTC)
- 30nA Shutdown mode (5 wakeup pins)
- 120nA Standby mode (5 wakeup pins)
- 420nA Standby mode with RTC
- 1.1μA Stop 2 mode, 1.4μA Stop 2 with RTC
- 100μA/MHz run mode
- Batch acquisition mode (BAM)
- 4μs wakeup from Stop 1 mode, 5μs from Stop 2 mode
- Brown out reset (BOR) in all modes except shutdown
- Interconnect matrix
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 80MHz, MPU, 100DMIPS/1.25DMIPS/MHz (Dhrystone 2.1), and DSP instructions
Clock Sources
- 4 to 48MHz crystal oscillator
- 32kHz crystal oscillator for RTC (LSE)
- Internal 16MHz factory-trimmed RC (±1%)
- Internal low-power 32kHz RC (±5%)
- Internal multispeed 100kHz to 48 MHz oscillator, auto-trimmed by LSE (better than ±0.25 % accuracy)
- 3 PLLs for system clock, USB, audio, ADC
IoT and Handheld Measurement Uses
- RTC with HW calendar, alarms and calibration
- LCD 8×40 or 4×44 with step-up converter
- 16x timers: 2x16-bit advanced motor-control, 2x32-bit and 5x16-bit general purpose, 2x16-bit basic, 2x low-power 16-bit timers (available in Stop mode), 2x watchdogs, SysTick timer
Up to 24 capacitive sensing channels: support touchkey, linear and rotary touch sensors
Up to 114 fast I/Os, most 5V-tolerant, up to 14 I/Os with independent supply down to 1.08V
Memories
- Up to 2MB Flash, 2 banks read-while-write, proprietary code readout protection
- Up to 640KB of SRAM including 32KB with hardware parity check
- External memory interface for static memories supporting SRAM, PSRAM, NOR and NAND memories
- Quad SPI memory interface
Sensor Polling
- 4x digital filters for sigma delta modulator
- Rich analog peripherals (independent supply)
  - 3×12-bit ADC 5Msps, up to 16-bit with hardware oversampling, 200μA/Msps
  - 2x12-bit DAC, low-power sample and hold
  - 2x operational amplifiers with built-in PGA
  - 2x ultralow-power comparators
Industrial Controls
- 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™