Person controlling her house with a smartphone

The STM32H503 microcontrollers extend the STM32 high performance portfolio and offer enhanced performance and better power efficiency. They feature 128 Kbytes of flash memory and 32 Kbytes of RAM. STM32H503 MCUs come in 25- to 64-pin packages, such as WLCSP, LQFP, and UFQFPN profiles.

The STM32H503 line is based on the Arm® Cortex®-M33 with digital signal processing (DSP) and a floating-point unit (FPU) running up to 250 MHz.

  • Performance: at 250 MHz, the STM32H503 delivers 375 DMIPS and a 1023 CoreMark score executing from the flash memory, with 0-wait states using ST’s ART Accelerator.
  • Embedded peripherals: up to 13 communication peripherals including I3C, FDCAN, and USB 2.0 full-speed host and device.
    • Power efficiency
    • 86 µA/MHz typical @VDD = 3.3 V and 25°C in run mode (peripherals off)
    • 54 µA typical in stop mode (low-power mode)
    • 3.5 µA typical in standby mode (low-power mode)
    • 380 nA typical in VBAT (battery voltage mode) with RTC (low-power mode)


Industrial arm
  • Programmable logic controllers (PLC)
  • Industrial motor control
  • Pumps and compressors
  • Air conditioner
  • Refrigerators and freezers
  • Central alarm system
  • Washing machines
Smart watch
  • Keyboard
  • Smartphones
  • IoT tags and tracking devices
  • Industrial communication
  • Lighting controls
  • Digital power
Thunder in a heart
  • CPAP and respirators
  • Dialysis machines
  • Pills distributors
  • Powered patient beds

Discover our portfolio

The STM32H503 enriches the STM32 product portfolio with more performance and better power efficiency.


  • More design freedom for developers and room to innovate at an affordable cost
  • Delivers performance in space-constrained IoT devices
  • Simplified connectivity solution for smart home devices
  • Optimized cost/performance trade-off based on ST’s optimized 40 nm process technology
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