Differentiate - Keysight Technologies InfiniiVision 6000L Series User Manual

Differentiate

d/dt (differentiate) calculates the discrete time derivative of the selected source.
You can use differentiate to measure the instantaneous slope of a waveform. For
example, the slew rate of an operational amplifier may be measured using the
differentiate function.
Because differentiation is very sensitive to noise, it is helpful to set acquisition
mode to Averaging in the Acquire Menu.
d/dt plots the derivative of the selected source using the "average slope estimate
at 4 points" formula. The equation is:
Where
d = differential waveform
y = channel 1, 2, 3, or 4, or g(t) (internal arithmetic operation) data points
i = data point index
Δt = point-to-point time difference
1 Press the [Math] key, press the Function softkey and select f(t), press the Operator
Keysight InfiniiVision 6000L Series Oscilloscopes User's Guide
d = y + 2y – 2y – y
i i+4 i+2 i-2
8Δt
softkey and select d/dt. Press the Source, Scale, or Offset sofkeys if you want to
change the source, scaling, or offset for the differentiate function.
• Source — selects the source for d/dt. (See
using g(t) as the source.)
• Scale — lets you set your own vertical scale factors for d/dt expressed in
units/second/division, where units can be V (Volts), A (Amps), or W (Watts).
Units are set in the channel Probe Menu. Press the Scale softkey, then turn
the Entry knob to rescale d/dt.
• Offset —lets you set your own offset for the dV/dt math function. The offset
value is in units/second where units can be V (Volts), A (Amps), or W (Watts)
and is represented by the center horizontal grid line of the display. Press the
Offset softkey, then turn the Entry knob to change the offset for d/dt.
A scale unit of U (undefined) will be displayed for scale and offset if the two
source channels are set to dissimilar units. Units are set using the channel's
Probe Units softkey.
Measurements and Math Functions
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