Tektronix IsoVu TIVP Series, Руководство пользователя

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Input coupling AC or DC
The TIVP sensor head contains both DC and DC Reject input coupling modes. By default, DC coupling is enabled; the
mode is switchable through the scope interface or PI command.
The DC input coupling setting provides a direct, DC coupled, electrical path in the sensor head; it accepts all types of
signals, including unchanging DC voltages, time-varying DC voltages, AC, and combinations of AC and DC.
When DC input coupling is selected, any applied offset is injected at the sensor head and the offset range depends on the
attached tip cable attenuation.
DC Reject input coupling setting provides an AC- only path in the sensor head, removing DC offset from any mixed signal to
view the AC component of the signal. DC reject is useful when you measure small amplitude signals superimposed on a
large differential offset component.
With DC Reject enabled, offset is applied at the oscilloscope input and is limited by the offset capability of the specific
Volts/Div setting on the oscilloscope multiplied by the selected tip attenuation.
Voltage range
The TIVP is designed to enable characterization of high frequency circuits with a wide range of differential voltages in the
presence of common mode voltages. Understanding the limits and differences between the voltage ratings as discussed in
this section is essential to optimize signal fidelity and measurement accuracy.
Although the common mode voltage range of the probe is very large (>60 kV), the differential input range is limited and
depends on the tip attenuation, the gain range selected, and the applied offset.
The input voltage conditions are divided into several different input ranges.
Common mode voltage range
TIVP sensor head is optically isolated from earth ground, making the common mode input range >60 kV. The differential
input range is more limited and refers to the signal that can be applied across the probe tip, regardless of the common mode
voltage.
Differential voltage range refers to the actual measurement that will appear on the oscilloscope screen when using IsoVu.
For accurate results, the measurement must fall within the range of any applied offset ±V
diff
range of the tip.V
meas
=V
offset
±V
diff
Offset voltage range
Offset voltage can be applied through the oscilloscope Vertical menu settings. The input offset capability of the probe
extends from ±25 V to ±2500 V depending on the tip used. This offset is applied at the sensor head of probe and can be
useful to bring applied signals within the dynamic range (V
diff
) of the probe.
Maximum non-destruct differential voltage range
The maximum non-destruct differential input range is the maximum differential voltage that can be applied to the input
without damaging the probe. This is a DC +peak AC rating (no portion of the differential input signal should exceed this
value). The maximum non-destruct differential voltage varies from ±20 V to ±2500 V depending of the sensor tip cable
being used. Exceeding these levels will cause permanent damage to components of the sensor head. Additionally, the
TIVPMX1X and SMA input also have VRMS limits.
Getting started
TIVP Series IsoVuTM Measurement System User Manual 34