ITEM NAME:Active Speaker Buzzer Module for Arduino works with Official Arduino Bo TwJ Lt Introduction to passive buzzer and active buzzer: The "source" here does not refer to the power source. It refers to the source of the shock. The characteristics of the passive buzzer are: (1) The passive internals do not have an oscillating source, so if the DC signal is used, it cannot be audible. It must be driven by a 2K-5K square wave (pwm); (2) The sound frequency can be controlled, and the effect of â€œDuo duo mi fa solassieâ€ can be made; (3) In some special cases, a control port can be multiplexed with the LED; The characteristics of the active buzzer are: (1) The active buzzer has an internal oscillation source, so it will be called as soon as it is energized. (2) The program control is convenient. The high and low level of the single chip can make it sound, but the passive buzzer can't. Introduction: (1) The module uses 9012 transistor drive (2) Operating voltage 3.3V-5V (3) Fixing bolt holes for easy installation (4) PCB size: 2.0cm * 2.3cm Interface definition: (1) VCC external 3.3V-5V voltage (which can be connected directly with the 5v microcontroller and 3.3v microcontroller) (2) GND External GND (3) I / O external microcontroller IO port Package includes:1 Pc.Introduction to passive buzzer and active buzzer The characteristics of the passive buzzer are The high and low level of the single chip can make it sound, but the passive buzzer can't. The characteristics of the active buzzer are.