Tektronix 071-0590-00 Singled-ended or Differential Operation, Selecting the Reference Data Mode

Reference

Singled-ended or Differential Operation

Analyzer clock and data inputs can be operated in a singled-ended or differential mode. Differential operation provides greater immunity to ground noise and EMI. Note that threshold setup applies to the clock and data inputs only when they are operated in the singled-ended mode. When the clock or data input is operated in the differential mode, its input threshold effectively becomes the average of the positive peak and negative peak voltage of the received true and complement signals.

Procedure to Configure CLOCK or DATA Inputs for Single-Ended Operation

1.Connect Clock signal to CLOCK input.

2.Connect Data signal to DATA input.

3.Connect cable from rear panel DATA THRESHOLD output to front panel DATA BAR input.

Selecting the Reference Data Mode

In most testing applications, the Analyzer is set up to compare the received data pattern with a data pattern generated internally by the Analyzer. However you may also set up the Analyzer to compare two externally generated patterns. This makes it possible to analyze framed or proprietary signals that cannot easily be simulated as long WORD patterns.

To configure the Analyzer for reference data testing, the primary or test signal must be connected to the Analyzer data input (which may be set up for singled- ended or differential operation) while the reference signal is connected to the REF DATA input. Then the Reference Data mode must be selected using the EXT key. Note that the reference signal must be generated by a singled-ended output.

Procedure for Selecting the Reference Data Mode

1.Connect a test signal to the Analyzer data input and a reference signal to the REF input.

2.Press the Analyzer EXT key to toggle the reference mode on. Verify that the EXT key turns on.

3.To de-select the reference mode, press the EXT key again. Verify that the EXT key turns off.

GB1400 User Manual 3-27