Memory map and peripheral set — what fits and what doesn't
The 32 KB Flash (32K x 8) is sized for compact firmware images — think a single-threaded sensor readout loop with a BLE stack or a simple motor-control algorithm. The 8 KB SRAM (8K x 8) supports moderate data buffers; if your application needs a large frame buffer or a real-time OS with multiple stacks, you'll bump against the ceiling. The 1 KB EEPROM (1K x 8) is a differentiator: it stores calibration constants, node IDs, and fault logs without wearing the Flash or adding an external part.
25 I/O in a 5x5 mm exposed-pad package
With 25 I/O lines in a 32-UFQFN package measuring 5x5 mm (exposed pad), this part fits on cramped PCBs for wearables, smart sensors, and compact control modules.
STMicroelectronics lists the STM32L041K6U6D with an active product status. There is no announced last-time-buy or end-of-life notice.