User guide

frequency range and the jitter amplitude range of the standard is given in the
preview. A description is displayed at the bottom of the Standard tab.
The last entry in the list is Browse…. Select this entry to load a file that contains
a user-defined standard. See “Setting the Standard” on page 454 for details.
To aggravate test conditions, the standard's test jitter amplitude can be increased
by Margin percent. The display shows a black line for the standard and a green
line for the new jitter amplitudes.
Select the Auto Frequencies checkbox to set frequencies that are recommended
for the selected standard. This list contains, for example, the edge frequencies of
the standard.
T I P
You can change single frequency points. Press Apply to accept the selected Auto
Frequencies setting and switch to the Frequency tab. In Manual mode, you can
edit the automatically calculated frequencies. If you do so, the Auto Frequencies
checkbox is automatically deselected.
Enter the number of test frequencies (Number of Steps) either on this tab, or on
the Frequency tab.
This is the creator's description of the selected standard. Standards provided by
Agilent are described by the following items:
T I P
Use the scroll bar if not all information is displayed.
• Document that describes the standard in detail. The document name usually
indicates the date or revision of the standard.
• Recommended settings for the test pattern like Bit Rate range, Pattern types
and voltage level ranges:
– Voltage Level from Standard: This is the peak-to-peak differential input
level range for the DUT as given in the standard.
– Voltage Level at PG (recom): This is the recommended output level at the
pattern generator to achieve the minimum voltage Level from Standard.
N O T E
This recommendation depends on the simulated intersymbol interference (ISI): The
minimum voltage Level from Standard is only met if the trace to simulate the ISI is
selected as in the description item Additional Jitter. Other settings of the ISI can
change the DUT's input level up to four times.
Jitter Tolerance Tests 8
Agilent J-BERT N4903B High-Performance Serial BERT 463
Margin
Auto Frequencies / Number of Steps
Description