Photodiodes and transistors are Employed in such things as proximity sensors, which detect little changes in voltage or existing across these products depending on the amount of light that falls on them. For example it is possible to place the transistor output about the low side and insert a pullup https://what-is-a-vibration-isola91357.goabroadblog.com/28215628/considerations-to-know-about-isolator-vibration-pad