Teledyne LeCroy QPHY-USB - Manual (Page 25)

QPHY-USB Software Option
QPHY-USB Operator’s Manual Rev F
25
Figure 22. HS Electrical Test Tool Setup for Device High-Speed Signal Quality
HIGH-SPEED SIGNAL QUALITY
Host and Hub Downstream High-Speed Signal Quality
1. Select Host or Hub in the Mode control and HS Downstream Signal Quality in the Test control of the
USB Test Wizard.
2. Follow the instructions on the right side of the menu. The port under test is connected to the SQ Host
section of the Test Fixture shown as follows.
3. The SMA cables are attached to the SMA connectors in this section of the fixture.
Figure 23. Signal Quality Host Section
The captured waveform should appear as follows. Cursors (dashed vertical lines in the image) must be placed on
either side of the packet as shown. Use the Cursors knobs on the oscilloscope’s front panel to adjust the position
of the cursors if necessary. The waveform between the cursors is processed by the USB-IF signal quality test
script to obtain an eye pattern and jitter measurements.