Tektronix 6 series, Printable Help

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Waveform integration
The math capabilities of the instrument 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:
■ Measuring power and energy, such as in switching power supplies.
■ 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:
Where: x(i) is the source waveform, y(n) is a point in the integral math waveform, scale is the output scale factor, and T is the
time between samples.
Since the resultant math waveform is an integral waveform, its vertical scale is in volt-seconds (its horizontal scale is in seconds).
The source signal is integrated over its entire record length; therefore, the math waveform record length equals that of the source
waveform.
Offset and position
When creating integrated math waveforms from live channel waveforms, consider the following:
■ You should scale and position the source waveform so that it is contained on screen. (Off screen waveforms may be
clipped, which will result in errors in the integral waveform.)
■ You can use vertical position and vertical offset to position your source waveform. The vertical position and vertical offset
will not affect your integral waveform unless you position the source waveform off screen so that it is clipped.
DC offset
The source waveforms that you connect to the instrument often have a DC offset component. The instrument integrates this
offset along with the time-varying portions of your waveform. Even a few divisions of offset in the source waveform may be
enough to ensure that the integral waveform saturates (clips), especially with long record lengths.
Measurement concepts
MSO54, MSO56, MSO58, MSO58LP, MSO64 Help 437