Tektronix 071-0590-00 user manual Analyzer Input Section

Functional Overview

Analyzer INPUT Section

The INPUT section of the Analyzer front panel contains the test signal NRZ data and clock inputs shown below.

DATA DATA REFERENCE DATA CLOCK CLOCK

∙CLOCK and DATA [inputs]: These inputs comprise the main test signal input to the Analyzer. DATA is the main NRZ data input to the Analyzer pattern detector and CLOCK is its corresponding clock signal. Both inputs have selectable input terminations. In addition, a variable amount of delay may be added to the DATA input to properly phase-align the clock and data signals. CLOCK and DATA may be used to terminate singled-ended clock and data outputs, respectively.

For single-endedapplications, the DATA input threshold is programmable. This requires an external cable connection from the rear panel DATA THRESHOLD output to the unused DATA input. Only the unused "DATA-BAR" input needs the threshold signal. The CLOCK input is self- biasing for single-ended applications.

∙CLOCK-BAR and DATA-BAR [inputs]: These are complimentary inputs to CLOCK and DATA. That is, CLOCK and CLOCK-BAR together comprise a differential clock input, while DATA and DATA-BAR together comprise a differential data input. When the Analyzer is connected to singled-ended clock and data signals, these inputs are not used.

Note: In DIFFERENTIAL applications, the programmed threshold voltage is not used.

∙REFERENCE DATA [input]: This is an input for a reference data signal. When the external reference mode is selected (LED in EXT key is on), the signal appearing at the REF DATA input will be used as the reference signal to perform bit error analysis instead of a (reference) pattern generated by the Analyzer's error detection circuit. Note that REF DATA uses the same clock signal as DATA, however different amounts of delay can be added to the DATA and REF DATA inputs to account for phase differences between the two signals.

GB1400 User Manual 2-13