Appendix B: Algorithms
TDS 684A, TDS 744A, & TDS 784A User Manual
B–5
Measurement Algorithms
The automated measurements are defined and calculated as follows.
Amplitude = High – Low
The arithmetic area for one waveform. Remember that one waveform is not
necessarily equal to one cycle. For cyclical data you may prefer to use the cycle
area rather than the arithmetic area.
if Start = End then return the (interpolated) value at Start.
Otherwise,
Area=
ŕ
End
Start
Waveform(t)dt
For details of the integration algorithm, see page B–12.
Amplitude (voltage) measurement. The area over one waveform cycle. For data
not cyclical, you might prefer to use the Area measurement.
If StartCycle = EndCycle then return the (interpolated) value at StartCycle.
CycleMean=
ŕ
EndCycle
StartCycle
Waveform(t)dt
For details of the integration algorithm, see page B–12.
Timing measurement. The duration of a burst.
1. Find MCross1 on the waveform. This is MCrossStart.
2. Find the last MCross (begin the search at EndCycle and search toward
StartCycle). This is MCrossStop. This could be a different value from
MCross1.
3. Compute BurstWidth = MCrossStop – MCrossStart
Amplitude
Area
Cycle Area
Burst Width
