Teledyne LeCroy QPHY-USB - Manual (Page 35)

QPHY-USB Software Option
QPHY-USB Operator’s Manual Rev F
35
HOST AND HUB DISCONNECT
Figure 33. Host Disconnect Section of Test Fixture
1. Select Host or Hub in the Mode control and HS Disconnect in the Test control of the USB Test Wizard.
2. Follow the instructions in the USB Test Wizard to acquire and measure the disconnect voltages. The
Disconnect Detected message is read from the USB-IF HS Electrical Test Tool dialog box. The traces for
normal and disconnect appears as follows:
Figure 34. Initial voltage before disconnect
Note: The Host trace is shown (previous). The same trace applies to Hub downstream ports.