Tektronix TDS 420A User Manual

Measuring Waveforms
3–74
TDS 420A, TDS 430A, TDS 460A & TDS 510A User Manual
Table 3–5: Measurement Definitions (Cont.)
Name Definition
Fall Time Timing measurement. Time taken for the falling edge of the first pulse in the waveform or gated
region to fall from a High Ref value (default = 90%) to a Low Ref value (default =10%) of its final
value.
Frequency Timing measurement for the first cycle in the waveform or gated region. The reciprocal of the
period. Measured in Hertz (Hz) where 1 Hz = 1 cycle per second.
High The value used as 100% whenever High Ref, Mid Ref, and Low Ref values are needed (as in fall
time and rise time measurements). Calculated using either the min/max or the histogram method.
The min/max method uses the maximum value found. The histogram method uses the most
common value found above the mid point. Measured over the entire waveform or gated region.
Low The value used as 0% whenever High Ref, Mid Ref, and Low Ref values are needed (as in fall
time and rise time measurements). May be calculated using either the min/max or the histogram
method. With the min/max method it is the minimum value found. With the histogram method, it
refers to the most common value found below the mid point. Measured over the entire waveform or
gated region.
Maximum Voltage measurement. The maximum amplitude. Typically the most positive peak voltage.
Measured over the entire waveform or gated region.
Mean Voltage measurement. The arithmetic mean over the entire waveform or gated region.
Minimum Voltage measurement. The minimum amplitude. Typically the most negative peak voltage.
Measured over the entire waveform or gated region.
Negative Duty Cycle Timing measurement of the first cycle in the waveform or gated region. The ratio of the negative
pulse width to the signal period expressed as a percentage.
NegativeDutyCycle +
NegativeWidth
Period
100%
Negative Overshoot Voltage measurement. Measured over the entire waveform or gated region.
NegativeOvershoot +
Low * Min
Amplitude
100%
Negative Width Timing measurement of the first pulse in the waveform or gated region. The distance (time)
between MidRef (default 50%) amplitude points of a negative pulse.
Peak to Peak Voltage measurement. The absolute difference between the maximum and minimum amplitude in
the entire waveform or gated region.
Period Timing measurement. Time it takes for the first complete signal cycle to happen in the waveform or
gated region. The reciprocal of frequency. Measured in seconds.
Phase Timing measurement. The amount one waveform leads or lags another in time. Expressed in
degrees, where 360 comprise one waveform cycle.
Positive Duty Cycle Timing measurement of the first cycle in the waveform or gated region. The ratio of the positive
pulse width to the signal period expressed as a percentage.
PositiveDutyCycle +
PositiveWidth
Period
100%

Tektronix TDS 420A Specifications

General

Brand	Tektronix
Model	TDS 420A
Category	Test Equipment
Language	English