Technical data

Agilent Technologies
71
N5416A USB 2.0 Compliance Test Option
Notes on Electrical Testing
4
Hub Hi-Speed Tests
Hub Hi-Speed Signal Quality Test - Upstream Facing Ports 73
Hub Hi-Speed Signal Quality Test - Downstream Facing Ports 78
Hub Jitter Test - Downstream Facing Ports 82
Hub Disconnect Detect 86
Hub Packet Parameters - Upstream Facing Port 90
Hub Receiver Sensitivity - Upstream Facing Port 97
Hub Repeater Test - Downstream Facing Port 106
Hub Repeater Test - Upstream Facing Port 111
Hub CHIRP Timing - Upstream Facing Port 117
Hub Suspend/Resume/Reset Timing - Upstream Facing Port 120
Hub Test J/K, SE0_NAK - Upstream Facing Port 128
Hub Test J/K, SE0_NAK - Downstream Facing Port 134
In addition to the high- speed electrical tests prescribed in this chapter,
the hub under test must also pass the following legacy electrical
compliance tests applicable to the high- speed hub:
• Full speed signal quality – Upstream and downstream facing ports.
• Low speed signal quality – Downstream facing ports only.
• Inrush current – Upstream facing port only.
NOTE
To give the automated test software more flexibility in making corner case measurements
(and improve test performance), the oscilloscope’s memory upgrade option is
recommended (Option 001 when ordered with the oscilloscope, or after purchase: E2680A
for the 5485xA Series oscilloscopes, or N5404A for the 80000 and 90000A Series
oscilloscopes).
Also, to reduce the bandwidth of the oscilloscope to just what is required by the USB-IF
(2 GHz for USB 2.0)—this can greatly reduce system measurement noise, allowing the
maximum measurement margin—the enhanced bandwidth software option is
recommended for the Agilent 54855A oscilloscope (Option 008), and the noise reduction
software option is recommended for the 80000 and 90000A Series oscilloscopes (Option
005 when ordered with the oscilloscope or N5403A after purchase).