STM32H503KBU6
Overview
The STM32H503KBU6 is a high-performance 32-bit microcontroller based on the Arm Cortex-M33 core with TrustZone, operating at speeds up to 250 MHz. It provides a compact 128KB Flash and 32KB RAM memory footprint in a small 5x5mm UFQFPN32 package, making it suitable for secure, space-constrained embedded systems. The device features an integrated FPU, DSP instructions, and enhanced security features including ECC on flash and SRAM.
Why Choose This Part
This MCU offers a unique balance of high-frequency performance (250 MHz) and advanced security in a very small package. The inclusion of ECC on both Flash and SRAM ensures high reliability for mission-critical applications, while the VOS0 power scaling allows for optimized efficiency at peak speeds.
Applications
Key Specifications
Getting Started
Developers can begin evaluation with the NUCLEO-H503RB development board and the STM32CubeH5 firmware package. Development is supported by the STM32Cube ecosystem, including STM32CubeMX for initialization and the STM32CubeIDE for coding and debugging via the integrated ST-LINK.
Dev Boards
Development boards and breakout modules featuring the STM32H503KBU6 or compatible chips — ready to use for prototyping.
STM32H503 Family
Comparing specs that differ across variants. The current part is highlighted.
| Part Number | I/O Pins | Core Processor | Package | ADC/DAC | Temp Range | Stock |
|---|---|---|---|---|---|---|
| STM32H503KBU6 (this part) | 24 | ARM Cortex-M33 | UFQFN-32 | A/D 10x12b SAR; D/.. | -40degC ~ 85degC (.. | 4,484 |
| STM32H503RBT6 | 49 | ARM Cortex-M33 | LQFP-64 | A/D 16x12b SAR; D/.. | -40degC ~ 85degC (.. | 1,449 |
| STM32H503CBU7TR Tape & Reel | 35 | ARM Cortex-M33F | UFQFN-48 | A/D 10x12b SAR; D/.. | -40degC ~ 105degC .. | 7,361 |
| STM32H503CBT6 | 35 | ARM Cortex-M33 | LQFP-48 | A/D 10x12b SAR; D/.. | -40degC ~ 85degC (.. | 2,550 |
| STM32H503CBU6 | 35 | ARM Cortex-M33 | UFQFN-48 | A/D 10x12b SAR; D/.. | -40degC ~ 85degC (.. | 1,482 |



