Introduction

A buzzer (sometimes called beeper) is an electronic component that can generate noise such as tones, buzz sound, and some simple melodies. No advanced melodies or sound can be generated, be aware that the buzzer is not a speaker; it is limited to simple noises only.

In fact, buzzers contain a lot of issues to discuss, they have many types: Magnetic, Electromechanical, Mechanical, Piezo (piezoelectric), each has a different properties from others, some are supplied with DC source and some are supplied with AC source.

Experimental Conditions

- 1 Uno board
- 1 Breadboard
- 1 USB cable
- 1 Buzzer (Active)
- Jumper wires

Principle

As a type of electronic buzzer with integrated structure, buzzers, which are supplied by DC power, are widely used in computers, printers, photocopiers, alarms, electronic toys, automotive electronic devices, telephones, timers and other electronic products for voice devices.

Buzzers can be categorized as active and passive ones (see the following picture). Turn the pins of two buzzers face up, the one with a green circuit board is a passive buzzer, while the other enclosed with a black tape is an active one.

Buzzer types

Fig1: active (at left side) and passive buzzers

The difference between an active buzzer and a passive buzzer is that in an active buzzer there is a built-in oscillating source, so it will make sounds when electrified. But a passive buzzer does not have such source, so it will not tweet if DC signals are used; instead, you need to use square waves whose frequency is between 2K and 5K to drive it. The active buzzer is often more expensive than the passive one because of multiple built-in oscillating circuits. In this experiment, an active buzzer is used.

Experimental Procedures

Step 1: Connect circuit as shown in the following Fig2. (Connect the digital pin to the positive pin of the buzzer; you can connect the buzzer to the µC without using a resistor)

Buzzer connection

Fig2: the connection of the buzzer


The corresponding schematic diagram is as shown in Fig3. (Schematic is generated by EAGLE)

eagle schematic
Fig3: the schematic


Step 2: Program the Arduino (download program from documents).
Step 3: Compile the program.
Step 4: Burn the program into the Uno board.

Now, you should hear the buzzer making sounds.

Experiment Summary

This experiment introduces a new useful electronic component, this component is useful for a simple sound applications that were mentioned in the principle section, it is so easy to control, you can control this element by changing the delay and the period of the pulse in your code, it is good if person got further in the buzzer issues, that allows him to build more applications with more options.

Documents:

1-Arduino progrme (code)
2-Eagle file