STMF401CCU6

STMF401CCU6-board

STM32F4 series breakout board

The breakout board is based on the STM32F401CCU6 microcontroller in a QFN-48 package, chosen for its high-performance ARM Cortex-M4 core and compact footprint, providing sufficient digital and communication interfaces for typical embedded applications while fitting within the 50 × 50 mm board area. Power regulation is handled by the TLV75801PDRV low-dropout linear regulator, selected for its compact SOT-23-5 package and ability to convert a 5 V input from USB or header to a stable 3.3 V supply required by the STM32F401 and peripherals. Peripheral pin mapping follows assignment specifications: five GPIO outputs, I2C1 on PB6/PB7, SPI1 on PA5/PA6/PA7, USART2 on PA2/PA3, and SWD interface on a 2×5 header including SWDIO, SWCLK, SWO, NRST, 3.3 V, and GND. To minimize routing complexity, peripherals are mapped to ensure all related pins are on the same side of the MCU, preventing excessive trace crossings and overlap. The reset button is connected to NRST with a parallel 0.1 μF capacitor, and a user LED is connected to PC13 via a 1.5 kΩ series resistor. Power and layout considerations prioritize clean routing and manufacturability. The 3.3 V rail is decoupled with four 100 nF capacitors near the MCU and a 10 μF bulk capacitor at the TLV75801PDRV output. The 8 MHz crystal is placed close to the MCU with a restricted area around its traces to prevent noise coupling. A solid GND pour covers both layers, connecting decoupling caps, mounting holes, and headers. Trace widths are 0.4 mm for power and 0.15–0.2 mm for signals, following standard PCB design practice.