Agilent Technologies DSO-X 4022A, User Manual

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140 Agilent InfiniiVision 4000 X-Series Oscilloscopes User's Guide
6
Digital Channels
you will discover the problem through random glitches or inconsistent
data measurements. Use the analog channels to view ringing and
perturbations.
Best Probing Practices
Because of the variables L, di, and dt, you may be unsure how much
margin is available in your measurement setup. The following are
guidelines for good probing practices:
• The ground lead from each digital channel group (D15–D8 and D7–D0)
should be attached to the ground of the device under test if any
channel within the group is being used for data capture.
• When capturing data in a noisy environment, every third digital channel
probe's ground should be used in addition to the channel group's
ground.
• High- speed timing measurements (rise time < 3 ns) should make use of
each digital channel probe's own ground.
When designing a high- speed digital system, you should consider designing
dedicated test ports that interface directly to the instrument's probe
system. This will ease measurement setup and ensure a repeatable method
for obtaining test data. The 01650- 61607 16- channel logic probe cable and
the 01650- 63203 termination adapter are designed to make it easy to
connect to industry- standard, 20- pin board connectors. The cable is a 2 m
logic analyzer probe cable, and the termination adapter provides the
proper RC networks in a very convenient package. These parts, as well as
the 1251- 8106 20- pin, low- profile, straight board connector, can be
ordered from Agilent Technologies.
To replace digital probe leads
If you need to remove a probe lead from the cable, insert a paper clip or
other small pointed object into the side of the cable assembly, and push to
release the latch while pulling out the probe lead.