In electronics, when describing a voltage or currentstep function, rise time (also risetime) refers to the time required for a signal to change from a specified low value to a specified high value. Typically, these values are 10
nd 90% of the step height. The output signal of a system is characterized also by fall time: both parameters depend on rise and fall times of input signal and on the characteristics of the system.
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In the approximation of a step function, the time required for a signal to change from a specified low value to a specified high value. Typically, these values are 10% and 90% of the step height. (188 )