ZD Series High Impedance Differential Probes
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recognizes the probe, provides proper termination and activates the probe
control functions in the user interface.
Connecting the Probe to the Test Circuit
To maintain the high-performance capability of the probe in measurement
applications, care must be exercised in connecting the probe to the test circuit.
Increasing the parasitic capacitance or inductance in the input paths may
introduce a “ring” or slow the rise time of fast signals. Input leads which form a
large loop area will pick up any radiated electromagnetic field which passes
through the loop and may induce noise into the probe input.
Using one of the available accessories makes a ZD series probe with its small
profile and low mass head ideally suited for applications in dense circuitry.
Operation with an Oscilloscope
When the probe is connected to any compatible Teledyne LeCroy oscilloscope,
the displayed scale factor and measurement values are automatically adjusted.
Turning the front panel Volts/Div
knob controls the oscilloscope’s scale factor
to give full available dynamic range up to 2.25 V/div.
Auto Zero
Auto Zero corrects for DC offset drifts that naturally occur from thermal effects
in the amplifier. The probe incorporates Auto Zero capability to remove the DC
offset from the probe's amplifier output to improve the measurement accuracy.
Auto Zero is invoked manually from the ZDxxxx dialog that appears when the
probe is connected to the oscilloscope.
Always perform Auto Zero after the probe is warmed up (recommended warm-
up time is 20 minutes). Depending on the measurement accuracy desired
and/or changes in ambient temperature where the probe is located, it may be
necessary to perform Auto Zero more often. If the probe is disconnected from
the oscilloscope and reconnected, repeat Auto Zero after a suitable warm-up
time.
CAUTION: Disconnect the probe from the circuit before Auto Zero, or
else any DC component that is part of the Signal to be measured will be
zeroed out.