STMicroelectronics STM32L0 series STM32L031E6Y6DTR, 32-bit ARM Cortex-M0+ MCU, 32MHz, 32KB Flash, 8K x 8 RAM, 1K x 8 EEPROM, 25-WLCSP (2.1x2.49), -40 to 85°C.
| Parameter | Value |
|---|---|
| Series | STM32L0 |
| Mounting type | Surface Mount |
| Oscillator type | Internal |
| Program memory type | FLASH |
| Voltage - supply (Vcc (Vdd)) | 1.8V ~ 3.6V |
| Operating temperature | -40°C ~ 85°C (TA) |
| Speed | 32MHz |
| Package | Tape & Reel (TR) |
| RAM size | 8K x 8 |
| Core size | 32-Bit Single-Core |
| EEPROM size | 1K x 8 |
| Peripherals | Brown-out Detect/Reset, DMA, POR, PWM, WDT |
| Connectivity | I²C, IrDA, LINbus, SPI, UART/USART |
| Number of i (O) | 20 |
| Core processor | ARM® Cortex®-M0+ |
| Case | 25-UFBGA, WLCSP |
| Data converters | A/D 10x12b |
| Program memory size | 32KB (32K x 8) |
The 25-WLCSP package (2.1x2.49 mm) is the smallest footprint in the family, built for space-constrained, battery-operated edge nodes: think sensor pods, wearable health monitors, and single-coin-cell IoT endpoints where every square millimeter of board area is budgeted.
Internal oscillator means you can skip the external crystal on cost-sensitive builds.
Within the STM32L0 series, the STM32L031E6Y6 (non-tape-and-reel suffix) is the same die in the same 25-WLCSP package — functionally identical, just shipped in a different carrier. For higher Flash or RAM you'd step up to the STM32L051 or STM32L071 density variants, but those change the memory map and may shift the pinout in the WLCSP. Stick with the STM32L031 base number for a guaranteed footprint match.