How to Use PicoBuck LED Driver: Examples, Pinouts, and Specs

The PicoBuck LED Driver is a versatile and compact board designed for driving high-power LEDs with ease and efficiency. It is capable of controlling up to three LEDs in series, making it an ideal choice for a variety of LED lighting applications such as architectural lighting, task lighting, and DIY LED projects. Its simplicity and power make it a popular choice for hobbyists and professionals alike.

• Input Voltage: 6V to 20V
• Output Current: Adjustable from 330mA to 660mA per channel
• Maximum Power Rating: 20W
• Number of Channels: 3
• Efficiency: Up to 95%
• PWM Dimming: Up to 20kHz
• Operating Temperature: -40°C to 85°C

1. Connecting Power: Connect a power supply to the VIN and GND pins, ensuring that the voltage is within the specified range (6V to 20V).

2. Attaching LEDs: Connect your high-power LEDs to the OUT1, OUT2, and OUT3 channels, with the anode to the output pin and the cathode to the GND.

3. Setting Current Limit: Adjust the onboard potentiometers to set the desired current limit for each channel (330mA to 660mA).

4. Enabling the Driver: Apply a high signal to the EN pin to enable the driver. A low signal will turn off the output to the LEDs.

5. Dimming Control: Use the CTRL pin to apply a PWM signal for dimming the LEDs. The frequency can be up to 20kHz.

• Ensure that the power supply voltage does not exceed the maximum input voltage rating.
• Always set the current limit to a safe level for your specific LEDs to prevent overheating and damage.
• Use proper heat sinking for the PicoBuck LED Driver and the LEDs to manage heat dissipation.
• When using PWM dimming, ensure that the frequency and duty cycle are within the specified limits for smooth operation.

• LEDs Not Lighting Up: Check the power supply connections and ensure that the EN pin is set high.
• Flickering LEDs: Verify that the PWM signal is within the correct frequency range and that the duty cycle is stable.
• Overheating: Ensure that adequate heat sinking is in place for both the driver and the LEDs.

Q: Can I drive LEDs that require more than 660mA? A: No, the PicoBuck LED Driver is designed with a maximum current limit of 660mA per channel.

Q: Is it possible to chain multiple PicoBuck drivers together? A: Yes, you can chain multiple drivers to control more than three LEDs, but each driver must be powered and controlled independently.

Q: How do I adjust the current limit? A: Use a small screwdriver to adjust the onboard potentiometers corresponding to each channel.

// Define the control pin for the PicoBuck LED Driver
const int pwmPin = 9; // Connect to the CTRL pin of the PicoBuck

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

void loop() {
  // Increase the brightness gradually
  for (int dutyCycle = 0; dutyCycle <= 255; dutyCycle++) {
    analogWrite(pwmPin, dutyCycle);
    delay(10);
  }
  // Decrease the brightness gradually
  for (int dutyCycle = 255; dutyCycle >= 0; dutyCycle--) {
    analogWrite(pwmPin, dutyCycle);
    delay(10);
  }
}

This example demonstrates how to gradually increase and decrease the brightness of the LEDs connected to the PicoBuck LED Driver using PWM dimming. The analogWrite function is used to send a PWM signal to the CTRL pin of the PicoBuck. The delay function is used to slow down the change in brightness for visibility.