Teledyne LeCroy AP034 - Manual (Page 17)

Operator’s Manual
922261-00 Rev A 11
NOTE The AP034 Active Differential Probe transmits the measured signal differentially through the
probe cable. This essentially eliminates signal degradation from ground loop effects within the
probe. However, creating a ground loop may introduce signal distortions in the test circuit itself, or
in any coaxial cable between the ADPPS power supply and the test instrument.
Selecting the Proper Range
The AP034 Active Differential Probe has a fixed gain of X1 (unity). Use of the ÷10 or ÷20 external
attenuators reduces the amplitude of the input signal when it is necessary to extend the dynamic
operating range of the probe. Attenuating the input signal increases both the differential mode
range and common mode range of the probe. Refer to the block diagram below.
Figure 3 AP034 Block Diagram
By using the plug-on attenuator, you can extend the attenuation range to ÷20. Do not use the ÷10
and ÷20 plug-on attenuators simultaneously. The maximum ranges are given in the following table:
Table 1. AP034 Dynamic ranges and input capacitance at different attenuator settings
÷1 Attenuation
(Probe Only)
÷10
Attenuation
÷100
Attenuation
Common Mode Range •±16 V ±42 V • ±42 V
Differential Mode Range* •±400 mV • ±4 V • ±8 V
*Offset moves the center point of this range.