It is additionally possible to turn on an Autotracking function. In C-mode, the autotracking function adjusts the offsets to null
out the low-frequency differential input seen by the probe amplifier, maximizing the common-mode dynamic range. In D
mode, the autotracking function adjusts the offsets to null out the low-frequency common-mode input seen by the probe
amplifier, maximizing the differential dynamic range.
Figure 9: Simplified Auto Tracking circuitry
The A and B input signals are buffered by the active probe tip buffer amplifier and passed down the probe main cable
assembly into the comp box probe amplifier input pins. The A and B input signals are picked off inside the probe amplifier
with large value resistors and output to an averaging filter capacitor as Sense_A and Sense_B signals. These sense signals
Theory of operation
TDP7700 Series TriMode™ Probes Technical Reference
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