STMicroelectronics has introduced the STM32C5 series, a new family of entry-level Arm Cortex-M33 microcontrollers built on a 40 nm flash process and clocked at up to 144 MHz. The MCUs deliver 593 CoreMark performance (4.12 CoreMark/MHz) while consuming less than 80 µA/MHz in dynamic operation, targeting smart home devices, industrial sensors, electronic locks, thermostats, wearables, robotic actuators, and computer peripherals.
The family spans from the compact STM32C531 with 64 KB SRAM and 128 KB flash in a 3 x 3 mm UFQFPN20 package, up to the STM32C5A3 with 256 KB SRAM and 1 MB flash in an LQFP144 package. Higher-end models add Ethernet MAC, Octo-SPI for external memory, dual AES with differential power analysis resistance, and Public Key Accelerator hardware. All variants include USB 2.0 Full-Speed, up to two CAN FD controllers, I3C support, CORDIC coprocessor for trigonometric operations, and an ART accelerator enabling zero-wait-state flash execution. Security features target SESIP3 and PSA Certified Level 3 compliance through hardware-backed cryptography, Hardware Unique Keys, and side-channel attack resistance on select models.
Development support includes three NUCLEO development boards: the NUCLEO-C542RC and NUCLEO-C562RE Nucleo-64 boards, plus the NUCLEO-C5A3ZG Nucleo-144 board with Ethernet and expanded connectivity. All boards feature integrated ST-LINK debugger/programmer and Arduino Uno V3 compatibility. The updated STM32CubeMX2 configuration tool provides faster access to reference code and code-size-optimized HAL2 drivers. Beyond ST's official tooling, the STM32 family benefits from a mature open-source ecosystem including Zephyr RTOS (which supports over 200 STM32 boards), PlatformIO for cross-platform development with multiple frameworks, the STM32duino Arduino core maintained by the community, and standard GNU toolchains including arm-none-eabi-gcc and OpenOCD for flashing and debugging, enabling makers to develop firmware using their preferred workflows on Linux, macOS, or Windows.
The STM32C5 series is now in production with pricing starting at $0.64 (€0.59) per unit for STM32C53x models in 10,000-unit quantities. The NUCLEO-C542RC and NUCLEO-C562RE boards are available for $20.62 (€19), while the NUCLEO-C5A3ZG is expected soon. Additional details are available in the press release.
