Tektronix TDSUSB2, Руководство пользователя

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Measurement Algorithms
Chirp Test Equipment Setup
The section used for this device test is Device SQ in the test fixture. To set up the
equipment for Chirp test, follow these steps:
1. Set the S6 switch to the Init position.
2. Use a standard USB cable with an A plug on one end and B plug on the
other end. Connect one end of the cable to the B socket on the Init port of
Device SQ section and the other end to the host port A socket.
3. Connect the A receptacle from the Device SQ test port to the unit under test
(device).
4. Connect the single-ended probes of the oscilloscope to the D+ and D– pins.
5. Select the measurement and select the command button to run the
application.
6. Disconnect and connect the unit under test (device) to the port and observe
the chirp signal on the oscilloscope.
7. Select OK after acquiring a waveform. Verify that it is a correct waveform.
Note: To avoid false triggering for the chirp signals while operating the test
fixture, it is recommended that you place the switch in the Init position and
connect the unit under test. This disables the switch bounce to the trigger.
212 TDSUSB2 Universal Serial Bus Measurement Package