Page 65 - Electronics Starter Kit_EN

16.5 Circuit Explanation

In this circuit we connected the pins 4 and 8 to 5V (it is okay if we did not connect pin 4), we
connected pin 5 to a 100nF capacitor to remove the noise through it to GND if exists (it is okay if
we remove it), pin 1 to GND, pin 3 to the Active Buzzer, to understand how this circuit works,let
us suppose that C1 is empty, so the voltage on pin 2 is almost zero, the Buzzer will makes a
sound, when the output is high, pin 7 will be almost 5V on it, so C1 will start to charge.

When the capacitor gets charged the voltage on pin 2 will be high, so the output will be zero, the
Buzzer will turn OFF, and pin 7 will be 0V so the capacitor will discharge.

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