How to Use Buzzer: Examples, Pinouts, and Specs

A buzzer is an audio signaling device that produces sound when an electric current passes through it. It is widely used in various applications such as alarms, timers, and notifications. Buzzers are available in two main types: active and passive. Active buzzers generate sound when powered, while passive buzzers require an external signal to produce sound. Their simplicity, low cost, and reliability make them a popular choice in electronic projects.

• Alarm systems (e.g., burglar alarms, fire alarms)
• Timers and reminders
• Notification systems in appliances (e.g., microwave ovens, washing machines)
• Electronic toys and gadgets
• Arduino and microcontroller-based projects

Below are the general technical specifications for a typical buzzer. Note that specific values may vary depending on the model and manufacturer.

Buzzers typically have two pins:

For active buzzers, simply applying a DC voltage will produce sound. For passive buzzers, an oscillating signal (e.g., PWM) is required.

1. Identify the Type of Buzzer: Determine whether the buzzer is active or passive. Active buzzers are easier to use as they only require a DC voltage, while passive buzzers need a signal source.
2. Connect the Pins:
   • Connect the positive pin of the buzzer to the power supply or signal source.
   • Connect the negative pin to the ground (GND) of the circuit.
3. Power the Circuit: For active buzzers, apply the appropriate voltage (e.g., 5V). For passive buzzers, use a microcontroller or signal generator to provide a PWM signal.

• Voltage Compatibility: Ensure the operating voltage of the buzzer matches your circuit's power supply.
• Current Limiting: If necessary, use a resistor to limit the current and protect the buzzer.
• Signal Frequency: For passive buzzers, use a frequency within the buzzer's range (e.g., 2kHz to 4kHz) to produce sound.
• Polarity: Always connect the positive and negative pins correctly to avoid damage.

Below is an example of how to connect and control a passive buzzer using an Arduino UNO.

• Connect the positive pin of the buzzer to Arduino pin 9.
• Connect the negative pin of the buzzer to GND.

// Example code to control a passive buzzer with Arduino UNO
// The buzzer will produce a tone at 2kHz for 1 second, then stop for 1 second.

#define BUZZER_PIN 9  // Define the pin connected to the buzzer

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

void loop() {
  tone(BUZZER_PIN, 2000);  // Generate a 2kHz tone on the buzzer pin
  delay(1000);             // Wait for 1 second
  noTone(BUZZER_PIN);      // Stop the tone
  delay(1000);             // Wait for 1 second
}

• Use a transistor or MOSFET to drive the buzzer if the current exceeds the microcontroller's pin limit.
• For passive buzzers, experiment with different frequencies to achieve the desired sound.

1. No Sound from the Buzzer:

   • Check the connections and ensure the buzzer is receiving the correct voltage.
   • Verify the polarity of the buzzer pins.
   • For passive buzzers, ensure the signal frequency is within the buzzer's range.

2. Buzzer Produces Weak or Distorted Sound:

   • Ensure the power supply provides sufficient current.
   • Check for loose or poor connections in the circuit.

3. Buzzer Overheats:

   • Verify that the operating voltage and current are within the buzzer's specifications.
   • Use a current-limiting resistor if necessary.

Q: Can I use a passive buzzer without a microcontroller?
A: Yes, you can use a signal generator or an oscillator circuit to drive a passive buzzer.

Q: How do I differentiate between an active and a passive buzzer?
A: Active buzzers typically have a built-in oscillator and produce sound when powered with DC voltage. Passive buzzers require an external signal and are usually smaller in size.

Q: Can I control the volume of a buzzer?
A: The volume of a buzzer is generally fixed. However, you can reduce the volume by lowering the supply voltage (within the operating range) or using a resistor in series.

By following this documentation, you can effectively integrate a buzzer into your electronic projects and troubleshoot common issues.