Any remaining stock in the channel is last-time-buy or surplus inventory.
80 MHz Cortex-M3 with a full peripheral set
That core speed puts it in the mid-range tier of Cortex-M3 devices — enough for real-time control loops, protocol stacks, and moderate DSP without needing a Cortex-M4. The 16-channel 10-bit ADC covers analog sensing for current, voltage, or temperature monitoring. The 108-BGA package (10x10 mm) with 72 I/O is a dense footprint.
Replacement reality — no pin-compatible drop-in
There is no official pin-compatible replacement for the LM3S5791-IBZ80-C5T from Texas Instruments. The Stellaris family was migrated to the Tiva C series, but the package and pinout changed. A board redesign is required to use a current-production Cortex-M4 part like the TM4C123 or TM4C129. The closest functional match in the same footprint class would be another 108-BGA Cortex-M3 or M4 from a different vendor, but that means a new layout, firmware port, and re-qualification. For a repair or a short-run production line, sourcing the original part through independent channels is the practical path.
Because the LM3S5791-IBZ80-C5T is obsolete, it is not stocked in volume by the manufacturer. Our sourcing desk can locate inventory across the independent and surplus distribution network — we quote against an RFQ with confirmed availability and current pricing. Expect to provide a target quantity and a date-code window if you have one. No lead-time number is available until we canvass the market; typical response is within one business day.