Appendix B: Algorithms
TDS 620A, 640A, & 644A User Manual
3. From , continue the search, looking for a crossing of . Update
if subsequent crossings are found. If a crossing is
found, it becomes the high rise time or . (Use linear interpolation if
necessary.)
4. =
High
HighRef
LowRe
f
Lo
w
THRTLR
Rise Time
Figure A-3: Rise Time
RMS:
Amplitude (voltage) measurement. The true Root Mean Square voltage.
If = then = the (interpolated) value at .
Otherwise,
=
For details of the integration algorithm, see below.
Integration Algorithm
The integration algorithm used by the digitizing oscilloscope is as follows:
is approximated by where: