Tektronix TDS5054, User Manual

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Creating and Using Math Waveforms
3- 142
TDS5000 Series User Manual
Figure 3- 41: Peak-peak amplitude measurement of a derivative waveform
Offset, Position, and Scale. The settings that you make for offset, scale, and
position affect the math waveform you obtain. Here are some tips for obtaining a
good display:
H
Scale and position the source waveform so that it is contained on the screen.
(Off-screen waveforms may be clipped, resulting in errors in the derivative
waveform).
H
Use vertical position and vertical offset to position your source waveform.
The vertical position and offset will not affect your derivative waveform
unless you position the source waveform off of screen so that it is clipped.
Waveform Integration.
The advanced math capabilities of the oscilloscope include
waveform integration . This allows you to display an integral math waveform that
is an integrated version of the acquired waveform.
Use integral waveforms in the following applications:
H
Measuring power and energy, such as in switching power supplies.
H
Characterizing mechanical transducers, as when integrating the output of an
accelerometer to obtain velocity.
The integral math waveform, derived from the sampled waveform, is computed
based on the following equation:
y ( n )
=
scale
n
Σ
i
=
1
x ( i )
+
x ( i
−
1 )
2
T