What is the 1/2 duty square wave?

If the user uses a passive piezoelectric buzzer or a passive electromagnetic buzzer, it is recommended to use 1/2 square wave in the input voltage and frequency conditions. Why use it? Because this condition can make the buzzer film inside achieve the highest amplitude, which means that the vibration of the sound reaches the limit and causes the buzzer to produce a high-energy sound output.

The 1/2 square wave is an AC signal, positive and negative half circumference, the upper and lower waveforms must be aligned, that is, 50% for each of the upper and lower waveforms. if there is one side of waveform runs off and becomes 40%, 30%, and 20%,then the AC signal will be close to the DC signal, which will make the buzzer's sound more and more muted.

The above-mentioned 1/2 square wave cannot be provided for users  manufacturers of 1/2 square-wave buzzer because it is an ac signal output by IC itself. The developers who write the IC programs generally know this point.If not, It is suggested that the user must read the specifications provided by the company in detail.