How to Use PWM fan: Examples, Pinouts, and Specs

The HighPi Pro 5V Fan - Software-Controlled by PiHut is a PWM (Pulse Width Modulation) fan designed for precise speed control. By varying the duty cycle of the power signal, this fan provides efficient cooling with reduced noise, making it ideal for applications where thermal management and noise reduction are critical.

• Computer Cooling: Effective cooling for CPUs, GPUs, and other components.
• Embedded Systems: Thermal management for Raspberry Pi, Arduino, and other microcontrollers.
• Industrial Equipment: Cooling for power supplies, motor drivers, and other industrial electronics.
• Home Automation: Quiet and efficient cooling for smart home devices.

1. Power Connection:

   • Connect the GND pin of the fan to the ground (GND) of your power supply or microcontroller.
   • Connect the VCC pin of the fan to the 5V power supply.

2. PWM Signal:

   • Connect the PWM pin to a PWM-capable pin on your microcontroller (e.g., Arduino UNO pin 9).

3. Tachometer Feedback (Optional):

   • Connect the Tach pin to a digital input pin on your microcontroller if you need speed feedback.

• PWM Frequency: Ensure the PWM frequency is within the range specified by the fan's datasheet (typically 25kHz).
• Duty Cycle: Adjust the duty cycle (0-100%) to control the fan speed. A higher duty cycle results in a higher fan speed.
• Power Supply: Ensure your power supply can provide sufficient current (0.2A) for the fan.
• Ventilation: Ensure proper ventilation around the fan to maximize cooling efficiency.

// Example code to control the HighPi Pro 5V Fan using Arduino UNO

const int pwmPin = 9; // PWM pin connected to the fan's PWM input

void setup() {
  pinMode(pwmPin, OUTPUT); // Set the PWM pin as an output
}

void loop() {
  // Set fan speed to 50% duty cycle
  analogWrite(pwmPin, 128); // 128/255 ~ 50% duty cycle
  delay(5000); // Run at 50% speed for 5 seconds

  // Set fan speed to 100% duty cycle
  analogWrite(pwmPin, 255); // 255/255 ~ 100% duty cycle
  delay(5000); // Run at 100% speed for 5 seconds

  // Set fan speed to 0% duty cycle (fan off)
  analogWrite(pwmPin, 0); // 0/255 ~ 0% duty cycle
  delay(5000); // Fan off for 5 seconds
}

1. Fan Not Spinning:

   • Solution: Check the power connections (GND and VCC). Ensure the PWM signal is being sent correctly.

2. Fan Speed Not Changing:

   • Solution: Verify the PWM signal frequency and duty cycle. Ensure the PWM pin is correctly configured.

3. Excessive Noise:

   • Solution: Ensure the fan is securely mounted and not obstructed. Check for any debris or obstructions.

• Check Connections: Ensure all connections are secure and correctly oriented.
• Verify Power Supply: Ensure the power supply provides a stable 5V and sufficient current.
• PWM Signal: Use an oscilloscope to verify the PWM signal if possible.
• Consult Datasheet: Refer to the fan's datasheet for specific details on PWM frequency and duty cycle requirements.

By following this documentation, users can effectively integrate and utilize the HighPi Pro 5V Fan - Software-Controlled in their projects, ensuring efficient cooling and noise reduction.