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 ITEM: "PASSIVE" BUZZER MODULE
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Characteristics:-
1/ The passive buzzer has no internal oscillation source, so if you use a DC signal, it cannot be made to buzz. A square wave of 2K~5K must be used to drive it.
2/ The sound frequency is controllable, and it can produce the effect of "multiple rice hair solasi".
3/ In some special cases, a control port can be reused with LED

Description:-
1/ module is driven by a 9012 triode
2/ Working voltage 3.3V-5V
3/ Weight: 6g
4/  With fixing bolt holes for easy installation
5/ Small board PCB size: 3.3cm * 1.3cm

Two module interface description (3-wire system)
1/  VCC external 3.3V-5V voltage (can be directly connected to 5v single-chip microcomputer and 3.3v single-chip microcomputer)
2/ GND external GND
3/  I/O external single-chip IO port

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 ITEM: "ACTIVE" BUZZER MODULE
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Characteristics:-
1/  The active buzzer has an internal oscillating source, so it will be called as soon as it is powered on.
2/  The program control is convenient. The single-chip microcomputer can make a sound with a high and low level, while the passive buzzer Can't do it.

Description:-
1/   The module is driven by S8550 transistors
2/   Working voltage is 3.3V-5V
3/   There are fixing bolt holes for easy installation
4/   Small board PCB size: 3.2cm * 1.3cm
5/   When the I/O port input low level, the buzzer Vocalize

Two module interface description (3-wire system)
1/  VCC external 3.3V-5V voltage (can be directly connected with 5v single-chip microcomputer and 3.3v single-chip microcomputer)
2/  GND external GND
3/  I/O external single-chip IO port