STM32F401CCU6 — ARM Cortex-M4 32-Bit Microcontroller

Overview

The STM32F401CCU6 is a high-performance 32-bit ARM Cortex-M4 microcontroller IC manufactured by STMicroelectronics. Operating at clock speeds up to $84\text{ MHz}$ with a hardware Floating Point Unit (FPU), it is the brain behind the widely popular "Black Pill" (WeAct Studio) development board.

Equipped with $256\text{ KB}$ of Flash memory, $64\text{ KB}$ of SRAM, a native USB 2.0 OTG Full-Speed controller, a 12-bit ADC ( $2.4\text{ MSPS}$ ), and advanced communication interfaces (I2C, SPI/I2S, USART), it offers significant performance gains over older Cortex-M3 boards (like the STM32F103 "Blue Pill").

Quick reference


CPU Core	ARM 32-bit Cortex-M4 with FPU & DSP instructions
Max Clock Frequency	$84\text{ MHz}$ (105 DMIPS)
Flash Memory	$256\text{ KB}$
SRAM	$64\text{ KB}$
Operating Voltage (`VDD`)	1.7 V to 3.6 V DC (3.3 V nominal)
Package	48-pin UFQFPN ( $7 \times 7\text{ mm}$ ) / "Black Pill" PCB
ADC Peripheral	1x 12-bit ADC (16 channels, $2.4\text{ MSPS}$ )
Communication Buses	1x USB 2.0 OTG FS, 3x USART, 4x SPI/I2S, 3x $I^2C$
Debug Interface	SWD (Serial Wire Debug) & JTAG

Pinout (Black Pill V3.0 Development Board Header)

text

                       ┌─────────────┐
                 [GND] │             │ [GND]
                [3.3V] │   STM32F4   │ [3.3V]
               [RESET] │ Black Pill  │ [VBAT]
       (PA0)   [ PA0 ] │  F401CCU6   │ [ PC13 ] (Onboard LED)
       (PA1)   [ PA1 ] │             │ [ PC14 ] (32.768kHz Crystal)
       (PA2)   [ PA2 ] │             │ [ PC15 ] (32.768kHz Crystal)
       (PA3)   [ PA3 ] │             │ [ PA8  ]
       (PA4)   [ PA4 ] │             │ [ PA9  ] (USART1 TX)
       (PA5)   [ PA5 ] │             │ [ PA10 ] (USART1 RX)
       (PA6)   [ PA6 ] │             │ [ PA11 ] (USB D-)
       (PA7)   [ PA7 ] │             │ [ PA12 ] (USB D+)
       (PB0)   [ PB0 ] │             │ [ PA15 ]
       (PB1)   [ PB1 ] │             │ [ PB3  ] (SWO)
       (PB2)   [ PB2 ] │             │ [ PB4  ]
       (PB10)  [ PB10] │             │ [ PB5  ]
       (PB12)  [ PB12] │             │ [ PB6  ] (I2C1 SCL)
       (PB13)  [ PB13] │             │ [ PB7  ] (I2C1 SDA)
       (PB14)  [ PB14] │             │ [ PB8  ]
       (PB15)  [ PB15] │             │ [ PB9  ]
                       └─────────────┘

Specifications

Parameter	Symbol	Min	Typ	Max	Unit	Conditions
Operating Supply Voltage	$V_{DD}$	1.7	3.3	3.6	V	DC supply
Run Mode Current	$I_{DD}$	—	20	35	mA	Run mode at 84 MHz
Stop Mode Current	$I_{stop}$	—	15	45	µA	Low power stop mode
Standby Mode Current	$I_{stby}$	—	2.4	5.0	µA	Backup domain powered
GPIO Output Current	$I_{IO}$	-25	—	+25	mA	Single GPIO pin
ADC Conversion Speed	$f_{ADC}$	—	2.4	—	MSPS	12-bit resolution

Wiring (ST-Link V2 SWD Programming Connection)

text

  ST-Link V2 Programmer            STM32F401 (Black Pill Header)
  ┌──────────────────┐            ┌─────────────────────────────┐
  │      3.3V        ├───────────►│ 3.3V                        │
  │      GND         ├───────────►│ GND                         │
  │      SWDIO       ├───────────►│ PA13 (SWDIO)                │
  │      SWCLK       ├───────────►│ PA14 (SWCLK)                │
  └──────────────────┘            └─────────────────────────────┘

Example (Arduino Core for STM32 - Blinking PC13 LED)

cpp

// Onboard LED on Black Pill is connected to PC13 (Active LOW)
const int ledPin = PC13;

void setup() {
  pinMode(ledPin, OUTPUT);
  Serial.begin(115200);
  Serial.println("STM32F401CCU6 Cortex-M4 Active!");
}

void loop() {
  digitalWrite(ledPin, LOW);  // Turn LED ON (Active Low)
  delay(250);
  digitalWrite(ledPin, HIGH); // Turn LED OFF
  delay(250);
}

Common mistakes

Confusing STM32F401CCU6 with STM32F411CEU6: The Black Pill board is sold in both STM32F401 ( $84\text{ MHz}$ , $256\text{ KB}$ Flash) and STM32F411 ( $100\text{ MHz}$ , $512\text{ KB}$ Flash) variants. Select the correct board definition in STM32CubeIDE or Arduino IDE.
Supplying > 3.6V to $V_{DD}$ : While many I/O pins are 5V tolerant, the power supply input ( $V_{DD}$ ) must be 3.3V DC. Exceeding 3.6V on $V_{DD}$ destroys the silicon.

Notes

STM32F401 vs STM32F103: STM32F401 features an ARM Cortex-M4 with hardware FPU at 84MHz, USB OTG, and 256KB Flash; STM32F103 is Cortex-M3 at 72MHz without FPU and with 64KB Flash.