STMicroelectronics STM32L0 series, STM32L051R6T6, ARM Cortex-M0+ 32-bit MCU, 32 MHz, 32 KB Flash, 8K x 8 RAM, 2K x 8 EEPROM, 51 I/O, 64-LQFP, -40°C to 85°C, 1.65V to 3.6V supply.
| Parameter | Value |
|---|---|
| Series | STM32L0 |
| Mounting | Surface Mount |
| Oscillator type | Internal |
| Program memory type | FLASH |
| Voltage - supply (Vcc (Vdd)) | 1.65V ~ 3.6V |
| Operating temperature | -40°C ~ 85°C (TA) |
| Speed | 32MHz |
| Package | Tray |
| RAM size | 8K x 8 |
| Core size | 32-Bit Single-Core |
| EEPROM size | 2K x 8 |
| Peripherals | Brown-out Detect/Reset, DMA, I²S, POR, PWM, WDT |
| Connectivity | I²C, IrDA, SPI, UART/USART |
| Number of i (O) | 51 |
| Core processor | ARM® Cortex®-M0+ |
| Case | 64-LQFP |
| Data converters | A/D 16x12b |
| Program memory size | 32KB (32K x 8) |
The STM32L051R6T6 is an ultra-low-power 32-bit MCU from ST's STM32L0 series, built around the ARM Cortex-M0+ core running at 32 MHz.
It is ROHS3 compliant. For a design starting today, this part is a safe anchor — no imminent end-of-life, no forced migration to a denser or more expensive variant.
Yes, it integrates 2 KB of EEPROM (2K x 8), which is useful for storing calibration constants or configuration data without an external serial EEPROM.
The STM32L151CBU6A is a pin-compatible alternative within the STM32L1 series, but it uses a Cortex-M3 core (same 32 MHz speed) and adds a 2-channel DAC and USB connectivity. The L051R6T6 is the lower-power, lower-cost entry point; the L151 trades some power efficiency for extra peripherals. Both are active, so dual-sourcing is possible if the BOM can accommodate the L151's slightly higher current draw.