2.6.2　Piezoelectric conversion

It is a conversion between pressure and voltage.Both piezoelectric ceramic chips and pressure sensors belong to this kind of converter.The common electronic scale is one of the applications with piezoelectric converter.In addition,microphones and speakers that we are familiar with also belong to this kind of converter.A microphone converts the pressure change of a sound wave into the corresponding voltage change,while a speaker performs the opposite conversion.That is the way to convert the changed electrical signal into the corresponding sound wave.Based on this kind of conversion method and some electrical instruments,we can also measure some physical quantities like sound pressure,sound speed,and sound frequency,etc.(https://www.daowen.com)