Musical Doorbell

Project Number: 15

Parts Needed For Circuit: B1, 6, SP, U1, D1, 5, S1, 2, R1, 3, S2, 1, 1, 2, 2, 2, 2

OBJECTIVE: To show how an integrated circuit can be used as a musical doorbell.

Description: Build the circuit shown on the left. When you close the slide switch (S1), the music integrated circuit (U1) may start playing one song then stop. Each time you press the press switch "doorbell button" (S2) the song will play again and stop. Even if you let go of the press switch (S2), the integrated circuit keeps the song playing until it has reached the end of the song. Musical integrated circuits are used to entertain young children in many of the toys and chairs made to hold infants. If the music is replaced with words, the child can also learn while they are entertained. Because of great advances in miniaturization, many songs are stored in a circuit no bigger than a pinhead.