How to Use Ultra-Small Size DC-DC 5V 3A BEC Power Supply Buck Step Down Module: Examples, Pinouts, and Specs

The Ultra-Small Size DC-DC 5V 3A BEC Power Supply Buck Step Down Module by Robu is a compact and efficient DC-DC converter designed to step down a higher input voltage to a stable 5V output. With a maximum current output of 3A, this module is ideal for powering low-voltage devices such as microcontrollers, sensors, and other electronic components. Its small size and high efficiency make it suitable for space-constrained applications.

• Powering microcontrollers (e.g., Arduino, Raspberry Pi, ESP32)
• Robotics and drones
• Battery-powered devices
• Portable electronics
• IoT devices and sensors

Below are the key technical details of the module:

The module has three pins for input and output connections:

1. Connect Input Voltage:

   • Connect the positive terminal of your power source (6V to 26V) to the VIN pin.
   • Connect the negative terminal of your power source to the GND pin.

2. Connect Output Load:

   • Connect the device or circuit requiring 5V to the VOUT pin.
   • Ensure the GND pin is also connected to the ground of your load.

3. Verify Connections:

   • Double-check all connections to avoid reverse polarity or short circuits.

4. Power On:

   • Turn on the power source. The module will regulate the input voltage to a stable 5V output.

• Input Voltage Range: Ensure the input voltage is within the specified range (6V to 26V). Exceeding this range may damage the module.
• Heat Dissipation: At higher currents (close to 3A), the module may generate heat. Use proper ventilation or a heatsink if necessary.
• Polarity Protection: The module does not have built-in reverse polarity protection. Double-check the polarity of your connections.
• Load Requirements: Ensure the connected load does not exceed the maximum output current of 3A.

The module can be used to power an Arduino UNO from a 12V battery. Below is an example circuit and code:

• Connect the VIN pin of the module to the positive terminal of the 12V battery.
• Connect the GND pin of the module to the negative terminal of the battery.
• Connect the VOUT pin of the module to the 5V pin of the Arduino UNO.
• Connect the GND pin of the module to the GND pin of the Arduino UNO.

// Example code to blink an LED connected to pin 13 of Arduino UNO
// Ensure the Arduino is powered via the 5V output of the DC-DC module

void setup() {
  pinMode(13, OUTPUT); // Set pin 13 as an output
}

void loop() {
  digitalWrite(13, HIGH); // Turn the LED on
  delay(1000);            // Wait for 1 second
  digitalWrite(13, LOW);  // Turn the LED off
  delay(1000);            // Wait for 1 second
}

1. No Output Voltage:

   • Cause: Incorrect input voltage or loose connections.
   • Solution: Verify that the input voltage is within the 6V to 26V range and check all connections.

2. Overheating:

   • Cause: Excessive current draw or poor ventilation.
   • Solution: Ensure the load does not exceed 3A. Use a heatsink or improve airflow around the module.

3. Output Voltage Not Stable:

   • Cause: Input voltage fluctuations or insufficient input power.
   • Solution: Use a stable power source and ensure the input voltage is at least 1V higher than the output voltage.

4. Module Not Working After Connection:

   • Cause: Reverse polarity or short circuit.
   • Solution: Check the polarity of the input connections. Replace the module if it is damaged.

Q1: Can this module be used to power a Raspberry Pi?
A1: Yes, the module can power a Raspberry Pi, but ensure the current draw does not exceed 3A.

Q2: Does the module have overcurrent protection?
A2: No, the module does not have built-in overcurrent protection. Use an external fuse if necessary.

Q3: Can I adjust the output voltage?
A3: No, the output voltage is fixed at 5V and cannot be adjusted.

Q4: Is the module suitable for automotive applications?
A4: Yes, as long as the input voltage is within the specified range and proper precautions are taken for heat dissipation.