The STM32H503xx devices are a powerful family of microcontrollers (STM32H5 series) based on the powerful ARM® Cortex®-M33 32-bit RISC core. They operate at a frequency of up to 250 MHz. The Cortex®-M33 core features a single-precision floating-point unit (FPU) that supports all Arm® single-precision data processing instructions and all data types. The Cortex®-M33 core implements a full set of digital signal processing (DSP) instructions and a memory protection unit (MPU) that enhances application security. The devices contain high-speed memory (128 KB dual bank flash memory and 32 KB SRAM), as well as a wide range of advanced I/O and peripherals connected to three APB buses, three AHB buses and a 32-bit multi-AHB bus matrix. They have multiple protection mechanisms for embedded flash memory and SRAM: Secure lifecycle management, write protection and concealed protection areas. The devices contain multiple peripherals that increase security: a HASH hardware accelerator and a true random number generator.