120 MHz Cortex-M4 with 2 MB Flash — memory headroom for complex firmware
It packs 2 MB of Flash and 640 KB of SRAM, giving firmware teams room for DSP libraries, dual-bank OTA updates, or a full RTOS with multiple application stacks without adding external memory.
144-ball UFBGA — layout and assembly considerations
Housed in a 144-UFBGA package with a 10x10 mm body, this is a fine-pitch BGA. The ball pitch is sub-0.8 mm, so the PCB requires at least four layers with microvias for fanout.
Active lifecycle — no near-term EOL risk
ST lists the STM32L4S9ZIJ6 with an active product status.