The STMicroelectronics access line ultra-low-power incorporates the high-performance Arm® Cortex®-M0+ 32-bit RISC core operating at a 32 MHz frequency, high-speed embedded memories (up to 32 Kbytes of Flash program memory, 1 Kbytes of data EEPROM and 8 Kbytes of RAM) and an extensive range of enhanced I/Os and peripherals. It provides high power efficiency for a wide range of performance.

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
Ultra-safe, low-power BOR brownout reset with 5 selectable thresholds
Programmable voltage detector PVD
USART, SPI supported
Serial wire debug supported
Up to 38 fast I/Os 31 I/Os 5V tolerant
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