The STM32L476xx 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 STM32L476xx devices embed high-speed memories (Flash memory up to 1 Mbyte, up to 128 Kbyte of SRAM), a flexible external memory controller (FSMC) for static memories (for devices with packages of 100 pins and more), 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 STM32L476xx devices embed several protection mechanisms for embedded Flash memory and SRAM: readout protection, write protection, proprietary code readout protection and Firewall. The devices offer up to three fast 12-bit ADCs (5 Msps), two comparators, two operational amplifiers, two DAC channels, an internal voltage reference buffer, a low-power RTC, two general-purpose 32-bit timer, two 16-bit PWM timers dedicated to motor control, seven general-purpose 16-bit timers, and two 16-bit low-power timers. The devices support four digital filters for external sigma delta modulators (DFSDM). In addition, up to 24 capacitive sensing channels are available. The devices also embed an integrated LCD driver 8x40 or 4x44, with internal step-up converter. They also feature standard and advanced communication interfaces. The STM32L476xx 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 VDD power supply when using internal LDO regulator and a 1.05 to 1.32V VDD12 power supply when using external SMPS 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, OPAMPs and comparators, 3.3 V dedicated supply input for USB and up to 14 I/Os can be supplied independently down to 1.08V. A VBAT input allows to backup the RTC and backup registers. Dedicated VDD12 power supplies can be used to bypass the internal LDO regulator when connected to an external SMPS. The STM32L476xx family offers six packages from 64-pin to 144-pin packages.
All features
Ultra-low-power with FlexPowerControl
1.71 V to 3.6 V power supply
-40 °C to 85/105/125 °C temperature range
300 nA in VBAT mode: supply for RTC and 32x32-bit backup registers
30 nA Shutdown mode (5 wakeup pins)
120 nA Standby mode (5 wakeup pins)
420 nA Standby mode with RTC
1.1 μA Stop 2 mode, 1.4 μA with RTC
100 μA/MHz run mode (LDO Mode)
39 μA/MHz run mode (@3.3 V SMPS Mode)
Batch acquisition mode (BAM)
4 μs wakeup from Stop mode
Brown out reset (BOR)
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 80 MHz, MPU, 100DMIPS and DSP instructions
Performance benchmark
1.25 DMIPS/MHz (Drystone 2.1)
273.55 CoreMark? (3.42 CoreMark/MHz @ 80 MHz)
Energy benchmark
294 ULPMark? CP score
106 ULPMark? PP score
Clock Sources
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)
3 PLLs for system clock, USB, audio, ADC
Up to 114 fast I/Os, most 5 V-tolerant, up to 14 I/Os with independent supply down to 1.08 V
RTC with HW calendar, alarms and calibration
LCD 8× 40 or 4× 44 with step-up converter
Up to 24 capacitive sensing channels: support touchkey, linear and rotary touch sensors
16x timers: 2x 16-bit advanced motor-control, 2x 32-bit and 5x 16-bit general purpose, 2x 16-bit basic, 2x low-power 16-bit timers (available in Stop mode), 2x watchdogs, SysTick timer
Memories
Up to 1 MB Flash, 2 banks read-while-write, proprietary code readout protection
Up to 128 KB of SRAM including 32 KB with hardware parity check
External memory interface for static memories supporting SRAM, PSRAM, NOR and NAND memories
Quad SPI memory interface
4x digital filters for sigma delta modulator
Rich analog peripherals (independent supply)
3x 12-bit ADC 5 Msps, up to 16-bit with hardware oversampling, 200 μA/Msps
2x 12-bit DAC output channels, low-power sample and hold
2x operational amplifiers with built-in PGA
2x ultra-low-power comparators
20x communication interfaces
USB OTG 2.0 full-speed, LPM and BCD
2x SAIs (serial audio interface)
3x I2C FM+(1 Mbit/s), SMBus/PMBus
5x USARTs (ISO 7816, LIN, IrDA, modem)
1x LPUART (Stop 2 wake-up)
3x SPIs (and 1x Quad SPI)
CAN (2.0B Active) and SDMMC interface
SWPMI single wire protocol master I/F
IRTIM (Infrared interface)
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?