Indoor noise detection circuit design

In today's era, noise pollution has become a common problem that people face in their daily lives. Under normal circumstances, when the sound intensity is below 30dB, it will be pleasant to the ear, and when it is above 80dB, it will be annoying. If it exceeds 100dB, it will affect people's mental state and cause a series of negative consequences, ranging from distraction to mental stress. Increase in size may lead to hearing loss or even epilepsy in severe cases. The noise intensity in a home environment is about 47dB, but Hi-Fi sound systems and high-volume televisions may increase the sound intensity to a level that endangers human health. To check the noise intensity in the room, we designed a circuit that detects and displays the noise intensity and also emits a flash warning when it exceeds the specified allowable intensity. As shown in the figure is the indoor noise detection circuit.