User's Manual

Operating Basics
20
P7225 2.5 GHz 10X Active Probe User Manual
Input Linear Dynamic Range
The probe head amplifier used by the P7225 has a limited linear
operating range. The usabl e dynamic range is ±4.0 V however, to
keep the input linearity error less than ±0.1%, you must limit the
apparent signal input voltage to ±3.75 V. If you use the full signal
input voltage of ±4.0 V, then the input line arity error increases to
±1.0%.
Use the DC offset adjustment to maintain the probe within the
dynamic range. The nominal offset adjustment range of the P7225 is
±10.0 V.
NOTE. The probe can tolerate input v oltages of ±30 V without
damage; however, the linearity error specification does not apply to
input voltages exceeding ±14.0 V (including any DC offset). See
Figure 4 on page 18.
Electrical Effects of Adapters
The probe tip adapters include d with your probe help connect to
different types of components. While t hese adapters make connec-
tions easier, be aware that the adapter you choose may affect the
signal that you are measuring, depending on a variety of factors,
including signal frequency, source impeda nce, and lead length.
Use the probe without adapters to optimize step and frequency
response. Using the probe tip adapters adds inductance and
capacitance, which increase step response and aberrations, and leads
to increased ripples in frequency response. These effects increase as
the source impedance increases and measured waveform risetimes
decrease.
Figure 5 on page 21 illustrates the typical effects on a given signal
using some of the adapt ers included with your probe.