The STM32L073VZI6 is an ultra-low-power 32-bit MCU from STMicroelectronics built around the ARM Cortex-M0+ core running at 32 MHz. It packs 192 KB of Flash program memory, 20 KB of SRAM, and a separate 6 KB EEPROM block, which saves an external EEPROM in many designs.
Memory headroom and firmware strategy
The 20 KB SRAM is tight for heavy data logging — budget for external SPI SRAM or use the 6 KB EEPROM for configuration parameters that survive resets. The EEPROM endurance is rated for 100k cycles per byte, so wear-leveling in firmware is advisable for frequently updated fields.
It is ROHS3 compliant.