Let's talk about the advantages of passive buzzers and active buzzers:

(A) The advantages of passive buzzers are:
1. Cheap;
2. The sound frequency is controllable, which can make the effect of "multi-meter hair solasi";
3. In some special cases, a control port can be multiplexed with LED.
(B) The advantages of active buzzers are:
The program control is convenient, and the direct DC voltage drive can be pronounced;
Generally, it is an integrated package, using high-temperature resistant materials, which can be directly soldered by wave soldering;
How to distinguish between an active buzzer and a passive buzzer?
1 eye: put the buzzer to the sky, if the circuit board is black indicates that there is a cause, if the circuit board is green indicates passive;
2 test: adjust the multimeter to the ohm block RX1 position, connect the positive pole of the buzzer with a black watch pen, touch it slowly, if it clicks,
A passive buzzer with a resistance value of 8Ω or 16Ω or 42Ω is a passive buzzer, and if it emits a continuous sound, it is an active buzzer.