Design and Improvement of 10-Second Countdown Timer

In this paper, we focus on the problem that the sound circuit keeps ringing when the countdown timer countdown to 0. To solve this problem, we have made many improvements. For the first time, we use Dingdong music chip to add Loudspeaker, after 10 seconds countdown, the loudspeaker "ding dong" stops three times; The buzzer is used for the second improvement, but the sound does not work normally, it sounds every 2 seconds, and finally it is successfully improved to make the buzzer stop automatically after ringing for a period of time as required by us. The paper gives the design schematic diagram, PCB diagram, and the actual circuit board display. Finally, the conclusion is summarized. The schematic diagram and PCB diagram improved for the first time with Ding Dong music chip and finally with buzzer can be directly applied because they have passed the experiment.