Settling time
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Settling time (aka centrelink time) stems from the system response and time constant.
Numerically for a 2nd order, closed loop system with step response,
Ts = -ln (tolerance fraction) / (natural freq*damping ratio)
Thus, settling time to within 2%=0.02 is:
Ts = 4 / n * wn
When an input is applied to a system, the output of the system will change as well. The time it takes for the system to settle within a certain value (tolerance say 1%) is called the settling time. This concept is often used in engineering. One example is analog amplifiers. Say the amplifier receives a large increase in voltage, "a step", the output of the amplifier will "slew" at its maximum rate of change to its destination for a fraction of the settling time. The rest of the settling time will be an expotential decay to the final value of the output.
Settling time of the amplifier is the time elapsed from the application of an ideal instantaneous step input to the time at which the amplifier output has entered and remained within a specified error band, usually symmetrical about the final value. Settling time includes a very brief propagation delay, plus the time required for the output to slew to the vicinity of the final value, recover from the overload condition associated with slewing, and finally settle to within the specified error.
