The access line ultra-low-power STM32L071xx microcontrollers incorporate the connectivity power of the universal serial bus (USB 2.0 crystal-less) with the high-performance ARM® Cortex®-M0+ 32-bit RISC core operating at a 32 MHz frequency, a memory protection unit (MPU), high-speed embedded memories (up to 192 Kbytes of Flash program memory, 6 Kbytes of data EEPROM and 20 Kbytes of RAM) plus an extensive range of enhanced I/Os and peripherals.
The STM32L071xx devices provide high power efficiency for a wide range of performance. It is achieved with a large choice of internal and external clock sources, an internal voltage adaptation and several low-power modes.
The STM32L071xx devices offer several analog features, one 12-bit ADC with hardware oversampling, two DACs, two ultra-low-power comparators, AES, several timers, one low-power timer (LPTIM), four general-purpose 16-bit timers and two basic timer, one RTC and one SysTick which can be used as timebases. They also feature two watchdogs, one watchdog with independent clock and window capability and one window watchdog based on bus clock.
Moreover, the STM32L071xx devices embed standard and advanced communication interfaces: up to three I2Cs, two SPIs, one I2S, four USARTs, a low-power UART (LPUART), and a crystal-less USB. The devices offer up to 19 capacitive sensing channels to simply add touch sensing functionality to any application.
The STM32L071xx also include a real-time clock and a set of backup registers that remain powered in Standby mode.
The ultra-low-power STM32L071xx devices operate from a 1.8 to 3.6 V power supply (down to 1.65 V at power down) with BOR and from a 1.65 to 3.6 V power supply without BOR option. They are available in the -40 to +125 °C temperature range. A comprehensive set of power-saving modes allows the design of low-power applications.
**Key Features**
Ultra-low-power platform
1.65 V to 3.6 V power supply
-40 to 125 °C temperature range
0.29 μA Standby mode (3 wakeup pins)
0.43 μA Stop mode (16 wakeup lines)
0.86 μA Stop mode + RTC + 20 KB RAM retention
Down to 93 μA/MHz in Run mode
5 μs wakeup time (from Flash memory)
41 μA 12-bit ADC conversion at 10 ksps
Core: ARM® 32-bit Cortex®-M0+ with MPU
From 32 kHz up to 32 MHz max.
0.95 DMIPS/MHz
Memories
Up to 192 KB Flash memory with ECC (2 banks with read-while-write capability)
20 KB RAM
6 KB of data EEPROM with ECC
20-byte backup register
Sector protection against R/W operation
Up to 4084 fast I/Os (3478 I/Os 5V tolerant)
Reset and supply management
Ultra-safe, low-power BOR (brownout reset) with 5 selectable thresholds
Ultra-low-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
Internal self calibration of 48 MHz RC for USB
PLL for CPU clock
Pre-programmed bootloader
USB, USART, I2C, SPI supported
Development support
Serial wire debug supported
Rich Analog peripherals
12-bit ADC 1.14 Msps up to 16 channels (down to 1.65 V)
12-bit ADC 1.14 Msps, up to 13 channels (down to 1.65 V)
2 x 12-bit channel DACs with output buffers (down to 1.8 V)
2x ultra-low-power comparators (window mode and wake up capability, down to 1.65 V)
Up to 19 capacitive sensing channels supporting touchkey, linear and rotary touch sensors
1x USB 2.0 crystal-less, battery charging detection and LPM
4x USART (2 with ISO 7816, IrDA), 1x UART (low power)
Up to 6x SPI 16 Mbits/s
3x I2C (2 with SMBus/PMBus)
11x timers: 2x 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, 2x 16-bit basic for DAC, and 2x watchdogs (independent/window)
