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Lesson 12 Buzzer
Introduction
Buzzers can be categorized as active buzzers and passive ones (See the following picture).
Components
-
1 * SunFounder Uno board
- 1 * USB data cable
- 1 * Buzzer module
- Several jumper wires
Experimental Principle
Place the pins of two buzzers face up and you can see the one with a green circuit board is
a passive buzzer, while the other with a black tape, instead of a board, is an active buzzer,
as shown below.
An active buzzer has 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 beep 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.
SunFounder
