How to Use Universal Barrel Jack Male: Examples, Pinouts, and Specs

The Universal Barrel Jack Male is a cylindrical power connector designed for reliable and secure power supply connections. It features a central pin for positive voltage and an outer sleeve for ground, making it a widely used component in electronic devices. This connector is ideal for providing DC power to a variety of circuits and devices, including development boards, small appliances, and DIY electronics projects.

• Powering development boards such as Arduino, Raspberry Pi (via adapters), and other microcontrollers.
• Supplying power to small electronic devices like routers, modems, and LED strips.
• DIY electronics projects requiring a standard DC power input.
• Prototyping circuits with external power supplies.

Below are the key technical details for the Universal Barrel Jack Male:

The Universal Barrel Jack Male has two main contact points:

1. Identify the Polarity: Ensure that the power supply matches the polarity of the barrel jack. The center pin is typically positive, and the outer sleeve is ground.
2. Connect to a Power Source: Insert the barrel jack into a compatible female connector or solder the wires to the appropriate terminals.
3. Verify Voltage and Current: Ensure the power supply voltage and current ratings are within the component's specifications (e.g., up to 24V DC and 5A).
4. Secure the Connection: If soldering, use heat shrink tubing or electrical tape to insulate the connections and prevent short circuits.

• Polarity Check: Always double-check the polarity of the power supply to avoid damaging your circuit.
• Avoid Overloading: Do not exceed the voltage or current ratings of the barrel jack to prevent overheating or failure.
• Use Proper Tools: When soldering, use a soldering iron with a fine tip and ensure clean, secure connections.
• Compatibility: Ensure the barrel jack dimensions (5.5 mm outer diameter, 2.1 mm inner diameter) match the female connector or device input.

The Universal Barrel Jack Male can be used to power an Arduino UNO via its DC power input. Below is an example of how to connect it:

1. Connect the center pin of the barrel jack to the positive terminal of a 9V DC power supply.
2. Connect the outer sleeve to the ground terminal of the power supply.
3. Insert the barrel jack into the Arduino UNO's DC input port.

If you're powering an Arduino UNO with the barrel jack, you can upload the following code to test the setup by blinking an LED:

// This code blinks the onboard LED on pin 13 of the Arduino UNO.
// Ensure the Arduino is powered via the barrel jack with a 9V DC supply.

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. Loose Connection: The barrel jack may not fit securely into the female connector.

   • Solution: Ensure the dimensions of the barrel jack match the female connector. Replace the connector if necessary.

2. Incorrect Polarity: Connecting the power supply with reversed polarity can damage the circuit.

   • Solution: Use a multimeter to verify the polarity of the power supply before connecting.

3. Overheating: The barrel jack becomes hot during operation.

   • Solution: Check that the voltage and current do not exceed the component's ratings. Ensure proper ventilation.

4. No Power to the Circuit: The device does not power on after connecting the barrel jack.

   • Solution: Verify the power supply is functioning correctly and that the connections are secure.

Q: Can I use this barrel jack for AC power?
A: No, the Universal Barrel Jack Male is designed for DC power only. Using it with AC power can damage the component and connected devices.

Q: What is the maximum cable length I can use with this barrel jack?
A: The maximum cable length depends on the current draw of your circuit and the wire gauge. For low current applications, a cable length of up to 2 meters is generally acceptable.

Q: Is this barrel jack waterproof?
A: No, the Universal Barrel Jack Male is not waterproof. Avoid using it in environments with high humidity or exposure to water.

Q: Can I use this barrel jack with a 12V battery?
A: Yes, as long as the battery's voltage and current output are within the component's specifications (up to 24V DC and 5A).