Adjusting the Frequency of Piezoelectric Buzzer

Piezoelectric buzzer is one of the feature-rich electronics components used to create sound. Ranging from the most common applications to advanced electronics appliances use this element. The most common use of this mechanism is buzzer alarm. It produces a definite frequency level accordingly the requirement.

Setting the Frequency of Piezoelectric Buzzer:

Most of the manufacturers don’t provide the frequency of the element. The frequency counter (oscilloscope) or a digital multimeter considered for the same. You have to connect it the recommended voltage for setting the frequency of this component. The manufacturers of piezo buzzers with built-in driving circuit provide directions to set the frequency. A variable resistance (e.g. potentiometer) used for changing the current to adjust the frequency. It is an alternative to the use of driving circuit.

Procedures to Changing the Frequency of Buzzer Alarm:

For doing the same, you will need the following ten components besides the Piezo buzzer.

1. 10 uF capacitor
2. 100k-ohm potentiometer
3. 2 4.7k-ohm resistors
4. 22k-ohm resistor
5. 741 op amp
6. Battery
7. Battery holder
8. Digital multimeter
9. Jumper wire
10. Solderless breadboard

Step – 1: Read the datasheet completely before going ahead. It will make it easy to understand the op amp chip and recognize the numbering system. Usually, to find the lead one, you have to look at the left of the chip’s side where it is marked with a notch.

Step – 2: Now you have to pick the solderless breadboard and fit the buzzer into it. You need not to worry regarding the plus and minus pins which could be found easily in singular columns. Try to place the buzzer precisely so that the plus and minus pins cover the gap of the breadboard’s top and bottom sections. Likewise, you have to attach the 741 chip and maintain a gap between the chip and piezoelectric buzzer.

Step – 3: Arrange the very top of the breadboard’s rows to zero voltage as ground. Otherwise, you can select any other column as ground, if there is no row available for required voltage connections. For the positive voltage which will be connected to the battery holder through red lead, set up a column or row. The black wire needs to be connected to the battery holder to ground.

Step – 4: Cable the minus / negative voltage point of the buzzer to ground. You can make this by connecting one end of the jumper wire into the negative side column. And the other end needs to be connected to the ground row’s one hole. In the same way, the op amp’s pin 4 insert into ground.

Step – 5: Connect the plus side of the buzzer and chip’s pin 6 through a wire. And the pin 7 of the chip needs to be connected with the row where the battery holder’s red lead already inserted.

Step – 6: Next wire the pin 2 of the op amp. Its one end must join with the potentiometer while other end of pot inserted into the column of pin 6. Another end of pin 2 joined with the capacitor. The capacitor’s 2nd end connected to the ground.

Step – 7: The op amp’s pin 3 has to be wired.

Step – 8: Complete and test the mechanism by adding the battery into the battery holder. Move the knob of the potentiometer to adjust its frequency.

Use the multimeter for checking the frequency of the buzzer alarm.

Author Resource:

Irving Blair is an acoustic equipment expert. He uses various acoustic products and reviews its performance. Recently he reviewed piezoelectric buzzer and recommend this buzzer alarm for various industrial usages.

Glorious Components is a manufacturing unit of industrial acoustic components in Mainland China. We produce wide range of acoustic products for various industrial applications. Our engineers and workmen are highly experienced and have detailed knowle