Glossary
Glossary–6 TDS 684A, TDS 744A, & TDS 784A User Manual
Knob
A rotary control.
Logic state trigger
The oscilloscope checks for defined combinatorial logic conditions on
channels 1, 2, and 3 on a transition of channel 4 that meets the set slope and
threshold conditions. If the conditions of channels 1, 2, and 3 are met then
the oscilloscope triggers.
Logic pattern trigger
The oscilloscope triggers depending on the combinatorial logic condition of
channels 1, 2, 3, and 4. Allowable conditions are AND, OR, NAND, and NOR.
Low
The value used as 0% in automated measurements (whenever high ref, mid
ref, and low ref values are needed as in fall time and rise time measure-
ments). May be calculated using either the min/max or the histogram
method. With the min/max method (most useful for general waveforms), it is
the minimum value found. With the histogram method (most useful for
pulses), it refers to the most common value found below the mid point. See
Appendix B: Algorithms for details.
Main menu
A group of related controls for a major oscilloscope function that the
oscilloscope displays across the bottom of the screen.
Main menu buttons
Bezel buttons under the main menu display. They allow you to select items
in the main menu.
Maximum
Amplitude (voltage) measurement of the maximum amplitude. Typically the
most positive peak voltage.
Mean
Amplitude (voltage) measurement of the arithmetic mean over the entire
waveform.
Minimum
Amplitude (voltage) measurement of the minimum amplitude. Typically the
most negative peak voltage.
NAND
A logic (Boolean) function in which the output of the AND function is
complemented (true becomes false, and false becomes true). On the
oscilloscope, that is a trigger logic pattern and state function.
Negative duty cycle
A timing measurement representing the ratio of the negative pulse width to
the signal period, expressed as a percentage.