Tektronix TDS5054, User Manual

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Creating and Using Math Waveforms
TDS5000 Series User Manual
3- 139
Table 3- 11: Math expressions and the math waveforms produced (Cont.)
To. . . and get this math waveform. . . Enter this math expression. . .
simulate AC coupling . . . AC component removed before integration
Channel 1
Source waveform
5.0 V
1.0 V
Intg(Ch1--Avg(Ch1)),
where
Ch1 is the waveform shown at left
Avg is the average function
1.05 V
1.00 V
0.95 V
+0.05 V
0.00 V
--0.05 V
AC integration math waveform
Sources.
Math waveforms can be created from:
H
Channel waveforms
H
Reference waveforms
H
Measurement scalars (automated measurements) that measure channel,
reference, or math waveforms, or histograms.
H
Math waveforms
Source Dependencies. In general, math waveforms that include sources as
operands are affected by updates to those sources:
H
Shifts in amplitude or DC level of input sources that cause the source to clip
also clip the waveform data supplied to the math waveform.
H
Changes to the vertical offset setting for a channel source that clip its data
also clip the waveform data supplied to the math waveform.
H
Changes to the acquisition mode globally affects all input channel sources,
modifying any math waveforms using them. For example, with the
acquisition mode set to Envelope, a Ch1 + Ch2 math waveform will receive
enveloped channel 1 and channel 2 data, and will also be an envelope
waveform.
H
Clearing the data in a waveform source causes a baseline (ground) to be
delivered to any math waveform that includes that source until the source
receives new data.
Expression Syntax. Build math waveforms using the Dual Waveform Math
controls (standard math) or the Equation Editor control window (advanced
math). To help you create valid math waveforms, these tools block most illegal
entries by disabling any window element that would create an invalid entry in
the math waveform expression.