Agilent Technologies N4906B Serial BERT User Manual page 53

Input and Output Ports
Agilent N4906B Serial BERT, User's Guide, October 2005
• Aux In
The signal at the Aux In port can be used to switch between
patterns A and B or to "blank" (suppress) the output signal.
Understanding the Pattern Generator's Output Ports
The pattern generator provides the following output ports:
• Data Out and Data Out
The data outputs serve as device stimuli and can be set up so that
they are compatible with a variety of logic families. With respect to
Data Out, Data Out has inverted logic.
• Clock Out and Clock Out
The clock outputs serve as frequency (bit rate) references and can
be set up so that they are compatible with a variety of logic families.
With respect to Clock Out, Clock Out has inverted logic.
• Trigger Out
This port allows you to connect a trigger for another device (for
example, an oscilloscope).
The complementary outputs can be used when:
• additional output capability is needed for an instrument such as an
oscilloscope or digital communication analyzer.
• your device requires differential inputs.
NOT E
The pattern generator's Data Out and Clock Out ports must be
terminated with 50 Ω if they are not connected.
Understanding the Output Protection Algorithm
The generator module offers a huge flexibility for external termination
schemes and external termination voltages to address common
technologies. For details, please refer to the Technical Data Sheet.
An internal protection algorithm continuously monitors the voltages
of clock and data output. It becomes active if the termination voltage is
wrongly adjusted.
NOT E The protection algorithm is not active if the termination voltage is
higher than +1.5 V.
The protection algorithm sets the output voltages to safe levels:
• V = termination voltage +1 V
high
Setting up the Pattern Generator
53