480 MHz Cortex-M7 with a surprise Flash budget
The STM32H750VBT6TR: The ARM Cortex-M7 core runs at 480 MHz. The 128 KB Flash is the program memory; the 1 MB RAM (1M x 8) is the workspace. The 100-LQFP package (14x14 mm) gives 82 I/O and access to the full peripheral set: dual CAN, Ethernet MAC, USB OTG, multiple SPI and I2C, plus an external memory interface for adding parallel Flash or SRAM.
128 KB Flash — design the boot path first
The 128 KB Flash is the spec that catches people out. This is not a part where you throw the full application into internal Flash. The intended use model is to run the core firmware from the internal Flash or from external QSPI, and execute performance-critical code or large data structures from the 1 MB RAM. The bootloader and a minimal kernel fit in Flash; everything else lives in RAM or external memory. If your team is used to the 2 MB Flash parts in the STM32H7 family, this one forces a different memory architecture.
Connectivity and peripherals — Ethernet is on the table
The Ethernet MAC answers the most common fit question directly — yes, this part supports Ethernet, with an external PHY on the MII/RMII interface.
The STM32L151 series is a 32 MHz Cortex-M3 part with a different performance and memory profile.