To measure longer intervals, the sample period must be increased.
Calculation
R esolution is formally defined as:
resolution = + /- (sample skew).
A high sample rate (100 MHz), coupled with low skew (plus or
minus 4 ns for both opposite and same direction transitions), gives
the timing analyzer very good resolution.
1
Improving the
Accuracy of Time
Interval
Measurements
You can improve the accuracy of an interval measurement by
making the measurement with a series of repetitive executions.
When a single execution is made, the resolution is equal to
+ /-(sample skew). When measuring a stable interval
using a series of repetitive executions, the accuracy of the
measurement improves by the following:
accuracy = + /-(((sample period)/sqrt(n)) + skew)
where:
sample period
is the sample period specified in the timing
analyzer trace specifications.
sqrt(n)
is the square root of the number of
executions included in the measurement.
skew
is the delay differences between input
channels.
A tenfold improvement (x10) is obtained in the accuracy of your
measurement when using one hundred repetitive executions for the
measurement.
Accurate Timing Measurements D-3
Содержание 64700 series
Страница 2: ......
Страница 19: ...Tables Table 9 1 Summary of Commands 9 4 Table 9 2 Command Assignments 9 5 Contents 11 ...
Страница 20: ...1 Notes 12 Contents ...
Страница 24: ...1 Notes 1 4 Introduction ...
Страница 106: ...1 Notes 4 36 Performance Measurements ...
Страница 118: ...Figure 5 8 True Demultiplexing 5 12 Using the External Analyzer ...
Страница 128: ...1 Notes 6 6 Timing Introduction ...
Страница 134: ...1 Notes 7 6 Timing Getting Started ...
Страница 168: ...1 Notes 8 34 Timing Using the Analyzer ...
Страница 176: ...1 compare This command specifies a post processing compare definition Syntax 9 8 Timing Commands ...
Страница 182: ...1 copy This command copies specifications displays or measurement data to selected output Syntax 9 14 Timing Commands ...
Страница 191: ...define DATA xbits 8 width 8 RETURN Related Commands delete rename threshold Timing Commands 9 23 ...
Страница 200: ...Examples execute repetitively RETURN Related Commands halt halt_repetitive_execution 9 32 Timing Commands ...
Страница 201: ...1 find This command finds a trigger like event in trace memory Syntax Timing Commands 9 33 ...
Страница 219: ...1 mark This command marks specified conditions in trace memory Syntax Timing Commands 9 51 ...
Страница 236: ...1 process_for_data This command limits the trace list display to specified samples Syntax 9 68 Timing Commands ...
Страница 254: ...1 trigger This command specifies trigger conditions Syntax 9 86 Timing Commands ...
Страница 261: ...Examples display timing_diagram RETURN waveform_size medium RETURN Related Commands present Timing Commands 9 93 ...
Страница 262: ...1 Notes 9 94 Timing Commands ...
Страница 280: ...1 Notes B 16 Timing Diagrams and Outputs ...
Страница 292: ...1 Notes C 12 Timing Messages ...