The characteristics of the passive buzzer is:
1 passive internal without shock source, so if use dc signal can't make it.Must use 2 k ~ 5 k square wave to drive it
For more than 2 sound frequency control, can make "m hair sola west" effect.
3 in some particular case, can reuse and LED a control
Module description
1 module driven by S8550 triode
2 working voltage of 3.3 V to 5 V
3 sets of fixed bolt hole, convenient installation
4 small board PCB size: 3.3 cm X 1.3 cm
2 Module interface specification (3 wire system)
1 VCC external 3.3 V to 5 V voltage (which can be directly connected to 5 V microcontroller and 3.3 V microcontroller)
2 GND external GND
3 I/O external microcontroller IO port