Agilent Technologies J-BERT N4903, User Manual

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3 In the Clock Logic Level list, select the logic family that is appropriate
for the clock input of your device.
When you modify the Data Logic Level or Clock Logic Level , the
instrument automatically sets the appropriate voltage levels and the
Termination voltage.
4
If necessary, change the data or clock termination voltage by
entering a new value. You can also use the front panel knob to change
the value.
The logic level automatically changes to Custom .
C A U T I O N
Selecting the wrong terminations may damage your device. See “Why Incorrect
Terminations Could Damage Your Device” on page 76 .
5
Connect the DUT's input ports to the Serial BERT's output ports.
C A U T I O N
Do not apply external voltages to the pattern generator outputs. For more
information, see
“AC Coupling and Bias Tees” on page 76 .
Output ports of the pattern generator that are not connected to another device must
be terminated with 50 Ohm to prevent the Serial BERT from damage.
Note that for unconnected ports, an internal protection algorithm automatically
reduces the output voltages to safe levels.
Adjust Output Levels (optional)
Data and clock offset and voltage levels can be adjusted. This is typically
done when you want to tune your BER measurement or stress the
device.
You can use the knobs on the Serial BERT's front panel to fine-tune the
data and clock amplitudes and offsets. If you want to set a specific value,
you can use the numeric keyboard.
To enter specific values for the data and clock outputs from the
keyboard:
1 Press PG Output Setup in the PG Setup menu to access the PG Output
Setup window.
2 Click into the field you want to change.
3 Enter the desired voltage using the numeric keyboard or the
respective front panel knob.
3
Setting up the Pattern Generator
80 Agilent J-BERT N4903 High-Performance Serial BERT