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

The Universal Barrel Jack Male is a cylindrical connector commonly used for power supply connections in electronic devices. It features a central pin for positive voltage and an outer sleeve for ground, making it a reliable and straightforward solution for delivering DC power. This component is widely used in prototyping, DIY electronics, and consumer devices due to its simplicity and compatibility with a variety of power sources.

• Powering Arduino boards, Raspberry Pi, and other microcontrollers
• Connecting DC power adapters to electronic circuits
• Prototyping and breadboard projects
• Consumer electronics such as routers, modems, and small appliances

The following table outlines the key technical details of the Universal Barrel Jack Male:

The Universal Barrel Jack Male has two main contact points:

1. Identify the Polarity: Ensure that the central pin is connected to the positive voltage (V+) and the outer sleeve is connected to ground (GND). Reversing the polarity may damage your circuit.
2. Connect to a Power Source: Insert the Universal Barrel Jack Male into a compatible female barrel jack or power socket. Ensure a snug fit for a reliable connection.
3. Wire the Leads: Solder wires to the central pin and outer sleeve terminals, or use a pre-wired version for convenience.
4. Verify Voltage and Current: Confirm that the power source matches the voltage and current requirements of your circuit.

• Check Compatibility: Ensure the barrel jack dimensions (5.5 mm outer diameter, 2.1 mm inner diameter) match the female connector.
• Avoid Overloading: Do not exceed the voltage and current ratings (24V DC, 5A) to prevent overheating or damage.
• Secure Connections: Use heat shrink tubing or electrical tape to insulate soldered connections and prevent short circuits.
• Polarity Protection: Consider adding a diode or polarity protection circuit to safeguard your device from accidental reverse polarity.

The Universal Barrel Jack Male is commonly used to power an Arduino UNO. Below is an example of how to connect it:

1. Use a 9V DC power adapter with a compatible female barrel jack.
2. Plug the male barrel jack into the Arduino UNO's power input port.
3. Ensure the adapter provides the correct polarity (center positive).

If you're powering sensors or modules through the Arduino UNO, you can use the following code to test the setup:

// Simple LED Blink Test
// Ensure the Arduino is powered via the Universal Barrel Jack Male

const int ledPin = 13; // Built-in LED pin on most Arduino boards

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

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

1. Loose Connection: The barrel jack may not fit snugly into the female connector.
   • Solution: Ensure the dimensions of the male and female connectors match (5.5 mm outer, 2.1 mm inner).
2. No Power to the Circuit: The device does not turn on after connecting the barrel jack.
   • Solution: Verify the polarity of the connection and ensure the power source is functioning.
3. Overheating: The barrel jack becomes hot during operation.
   • Solution: Check that the current draw does not exceed 5A and that the voltage is within the rated range.
4. Intermittent Power: The circuit powers on and off sporadically.
   • Solution: Inspect the solder joints or wire connections for stability and re-solder if necessary.

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 may damage the component or connected devices.

Q: Is this barrel jack compatible with all Arduino boards?
A: Most Arduino boards, including the UNO, use a 5.5 mm outer diameter and 2.1 mm inner diameter barrel jack. Verify the specifications of your specific board to ensure compatibility.

Q: How do I prevent reverse polarity damage?
A: Use a diode or a polarity protection circuit in your design to safeguard against accidental reverse polarity connections.

Q: Can I use this barrel jack for high-power applications?
A: The barrel jack is rated for up to 24V DC and 5A. For higher power applications, consider using connectors with higher ratings.