Tektronix TDSUSBF, Инструкция по эксплуатации

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TDSUSBF Test Fixture
TDSUSBF USB 2.0 Compliance Test Fixture Instructions
5
Connections and Switch Settings
Use Figure 1 on page 6 and Table 2 on page 7 to prepare the fixture for
specific tests.
NOTE
. Other Tektronix probes may also be suitable. Refer to the Test Equipment
section of this document to verify compatibility of alternative probes.
For more tests, the following oscilloscope configuration is recommended:
CH 1—P6248 Differential probe connected to D+ and D-- (High speed) or
P6245 single-ended probe connected to D+ (Low Speed (LS)/Full Speed
(FS))
CH 2—P6245 single-ended probe connected to D-- (LS/FS)
CH 3—On the adjacent channel trigger source (LS/FS), P6245 single-ended
probe connected to D+ for full speed testing, D-- for low speed testing
CH 4—Current probe for Inrush measurements
The Initialize and Test switch (S6) is a two-position switch used to place the test
fixture into initialize status or to test configurations for the following tests:
H
Device high speed TDR
H
Device high speed receiver sensitivity
H
Device high speed signal quality
For upstream high speed signal quality testing:
There are two sets of stake pins in the high-speed signal quality segment.
The set of stake pins (J310) adjacent to the relay pads are intended for use in
Signal Quality testing. The set of stake pins (J34) closest to the A receptacle
is intended for use in Packet Parameter, Suspend, Resume and Reset tests.
In the initialize position, the signal is routed through the fixture, from the
input to the output connectors to permit placing the DUT into test packet or
other test modes. In this mode, the signal is not present on the signal quality
pins (J310) next to the relay pads until the INIT/Test switch is placed into
the test position. To verify whether the signal is present in INIT mode, place
your probe on the set of stake pins (J34) next to the A receptacle. Return the
probe to the signal quality pins to conduct the signal quality test.
In the test position, the signal is passed from the DUT and is terminated into
precision 45 ohm resistors on the fixture. To probe the signal, connect the
middle two header pins located near the relay pads.
Switch S6 (Init/Test)