Fall time

When the input power to a power supply circuit or similar is cut off, the output voltage decreases over a certain period of time due to transient phenomena and eventually reaches 0. Of the time until this output voltage reaches 0, it refers to the time during which it falls from 90% to 10%. It is one of the time indicators showing transient characteristics when the input power is shut off. The longer the fall time, the higher the output stability against momentary power outages or voltage drops of the input power. If there are many capacitive components in the circuit, the fall time tends to become longer due to the discharge time.