STMicroelectronics, 32bit ARM Cortex M0+, STM32L0 Microcontroller, 32MHz, 32 kB Flash, 32-Pin LQFP

The access line ultra-low-power STM32L031x4/6 family 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) plus an extensive range of enhanced I/Os and peripherals.
The STM32L031x4/6 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 STM32L031x4/6 devices offer several Analogue features, one 12-bit ADC with hardware oversampling, two ultra-low-power comparators, several timers, one low-power timer (LPTIM), three general-purpose 16-bit timers, one RTC and one SysTick which can be used as timebases.
Moreover, the STM32L031x4/6 devices embed standard and advanced communication interfaces: one I2C, one SPI, one USART, and a low-power UART (LPUART).