O
PERATOR
’
S
M
ANUAL
Determining Differential Time Measurements
The DDA-5005 enables accurate differential time measurements between two traces: for example, propagation,
setup and hold delays (see Figure 3).
he
data signals to be specified.
Parameters such as Delta c2d± require the transition polarity of t
clock and
Figure 3
e any spurious transition that does not exceed the
erval. In Figure 3, Delta c2d- (1, 2) measures the time interval separating the rising
t negative transition of the data signal. Similarly, Delta c2d+ (1, 2)
e trigger and the next transition of the data signal.
ee the comments in the
Notes
column of the table.
Moreover, a hysteresis range may be specified to ignor
boundaries of the hysteresis int
edge of the clock (trigger) from the firs
measures the time interval between th
Level and Slope
For several time based measurements, you can choose positive, negative, or both slopes to begin parameter
measurements. For two-input parameters, such as Dtime@level, you can specify the slope for each input, as well
as the level and type (percent or absolute).
List of Parameters
The following table describes the instrument parameters. Availability of some parameters depends on the options
installed. S
Parameter
Description
Definition
Notes
Amplitude
Measures the difference between
upper and lower levels in two-level
signals. Differs from pkpk in that
noise, overshoot, undershoot, and
ringing do not affect the
measurement.
top - base
On signals not having two major
levels (such as triangle or saw-
tooth waves), returns same value
as pkpk.
Standard parameter.
Amplitude asymmetry between taa+
and taa-
1 - |(taa+ - taa-)|/(taa+ -
taa-)
Hysteresis argument used to
discriminate levels from noise in
data.
Available with DDM2 option.
Standard in DDA-5005A.
Ampl asym
ACSN
Auto-correlation Signal-to-Noise
provides a signal-to-noise ratio for
periodic waveforms.
Available with DDM2 option.
Standard in DDA-5005A.
Area
Integral of data: Computes area of
waveform between cursors relative
to zero level. Values greater than
zero contribute positively to the
area; values less than zero
negatively.
Sum from first to last of
data multiplied by
horizontal time between
points
Standard parameter.
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