The LM3S1751-IQC50-A2T is a Stellaris® ARM® Cortex®-M3S 1000 series microcontroller running a 32-bit single-core at 50 MHz.
That means TI is no longer actively supporting this part for new projects, and the window for last-time-buy orders is closing — or already closed. For existing production, you are looking at the surplus and independent distribution channel to fill BOM lines.
Connectivity and peripherals for industrial control
Four 10-bit ADC channels handle analog feedback from potentiometers or current shunts. The brown-out detect and POR circuits keep the core from running wild during a supply dip — useful in an environment with motor starts or contactor dropout.