16-bit MSP430 with 4 KB Flash — sizing the firmware budget before you commit
It packs 4 KB of program Flash and 256 bytes of RAM — enough for a single control loop, periodic sensor reads, or a simple user interface, but tight enough that a firmware engineer should map the memory layout before the first prototype spins.
No boost converter or LDO needed in a coin-cell remote sensor — that saves board area and quiescent draw. The POR (power-on reset) and WDT peripherals keep the startup sequence reliable even as the battery voltage sags toward 1.8 V.
The 20-TSSOP package in a 4.4 mm wide body keeps the PCB footprint small, and at 0.65 mm pitch it is still reworkable with a standard fine-tip iron.
Active lifecycle — no LTB chase needed
TI lists the MSP430F1121AIPWR as Active (current production).