Two module interface description (3-wire system)
VCC is externally connected with 3.3V-5V voltage (it can be directly connected with 5v single-chip microcomputer and 3.3v single-chip microcomputer)
GND external GND 3 I/O is connected to the IO port of the single chip computer
module is driven by S8550 triode
Working voltage 3.3V-5V
It is equipped with fixing bolt holes for easy installation
Small PCB size: 3.2cm * 1.3cm
When I/O port input low level or high level, buzzer sounds