This is information on a product in full production.
March 2018 DS10668 Rev 6 1/126
STM32L031x4 STM32L031x6
Access line ultra-low-power 32-bit MCU Arm
®
-based
Cortex
®
-M0+, up to 32KB Flash, 8KB SRAM, 1KB EEPROM, ADC
Datasheet - production data
Features
•
Ultra-low-power platform
– 1.65 V to 3.6 V power supply
– -40 to 125 °C temperature range
– 0.23 µA Standby mode (2 wakeup pins)
– 0.35 µA Stop mode (16 wakeup lines)
– 0.6 µA Stop mode + RTC + 8 KB RAM retention
– Down to 76 µA/MHz in Run mode
– 5 µs wakeup time (from Flash memory)
–41µA
12-bit ADC conversion at 10 ksps
•
Core: Arm
®
32-bit Cortex
®
-M0+
– From 32 kHz up to 32 MHz max.
– 0.95 DMIPS/MHz
•
Reset and supply management
– Ultra-safe, low-power BOR (brownout reset)
with 5 selectable thresholds
– Ultralow power POR/PDR
– Programmable voltage detector (PVD)
•
Clock sources
– 1 to 25 MHz crystal oscillator
– 32 kHz oscillator for RTC with calibration
– High speed internal 16 MHz factory-trimmed RC
(+/- 1%)
– Internal low-power 37 kHz RC
– Internal multispeed low-power 65 kHz to
4.2 MHz RC
– PLL for CPU clock
•
Pre-programmed bootloader
– USART, SPI supported
•
Development support
– Serial wire debug supported
•
Up to 38 fast I/Os (31 I/Os 5V tolerant)
•
Memories
–
Up to
32-Kbyte Flash with ECC
– 8-Kbyte RAM
– 1-Kbyte of data EEPROM with ECC
– 20-byte backup register
– Sector protection against R/W operation
–
•
Rich Analog peripherals
– 12-bit ADC 1.14 Msps up to 10 channels (down
to 1.65 V)
– 2x ultra-low-power comparators (window mode
and wake up capability, down to 1.65 V)
•
7-channel DMA controller, supporting ADC, SPI,
I2C, USART, Timers
•
5x peripherals communication interface
•
1x USART (ISO 7816, IrDA), 1x UART (low power)
•
Up to 2 SPI interfaces, up to 16 Mbits/s
•
1x I2C (SMBus/PMBus)
•
8x timers: 1x 16-bit with up to 4 channels, 2x 16-bit
with up to 2 channels, 1x 16-bit ultra-low-power
timer, 1x SysTick, 1x RTC and 2x watchdogs
(independent/window)
•
CRC calculation unit, 96-bit unique ID
•
All packages are ECOPACK
®
2
Table 1. Device summary
Reference Part number
STM32L031x4
STM32L031G4, STM32L031K4,
STM32L031C4, STM32L031E4,
STM32L031F4
STM32L031x6
STM32L031G6, STM32L031K6,
STM32L031C6, STM32L031E6,
STM32L031F6
UFQFPN28 4x4 mm
UFQFPN32 5x5 mm
UFQFPN48 7x7 mm
LQFP32/48
7x7 mm
WLCSP25
2.097x2.493 mm
TSSOP20
169 mils
www.st.com
Contents STM32L031x4/6
2/126 DS10668 Rev 6
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.1 Device overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
2.2 Ultra-low-power device continuum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3 Functional overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.1 Low-power modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.2 Interconnect matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.3 Arm
®
Cortex
®
-M0+ core . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
3.4 Reset and supply management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.4.1 Power supply schemes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.4.2 Power supply supervisor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.4.3 Voltage regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.4.4 Boot modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.5 Clock management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.6 Low-power real-time clock and backup registers . . . . . . . . . . . . . . . . . . . 25
3.7 General-purpose inputs/outputs (GPIOs) . . . . . . . . . . . . . . . . . . . . . . . . . 25
3.8 Extended interrupt/event controller (EXTI) . . . . . . . . . . . . . . . . . . . . . . . . 26
3.9 Memories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.10 Direct memory access (DMA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.11 Analog-to-digital converter (ADC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
3.12 Temperature sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
3.12.1 Internal voltage reference (V
REFINT
) . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
3.13 Ultra-low-power comparators and reference voltage . . . . . . . . . . . . . . . . 28
3.14 System configuration controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
3.15 Timers and watchdogs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.15.1 General-purpose timers (TIM2, TIM21 and TIM22) . . . . . . . . . . . . . . . . 29
3.15.2 Low-power timer (LPTIM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.15.3 SysTick timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.15.4 Independent watchdog (IWDG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.15.5 Window watchdog (WWDG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
