Figure 7: TekFlex probe tip inputs
Max non-desctruct input voltage
The maximum input voltage is the maximum voltage to ground that the inputs can withstand without damaging the probe
input circuitry. The TekFlex active probe tips include some over-voltage protection circuitry at the probe tip signal inputs.
(See
Figure 7: TekFlex probe tip inputs
on page 9.) Transient voltage suppression diodes, Da and Db, provide bidirectional
voltage clamping of signals applied to the probe tip inputs. These TVS diodes limit potential ESD damage as well as signal
over-voltage damage to the active tip buffer amplifier device.
CAUTION: To avoid damaging the inputs of the probe, do not apply more than ±15 V (DC + peak AC) between
either probe input and ground.
CAUTION: To avoid ESD damage to the probe, always use an antistatic wrist strap (provided with your probe), and
work at a static-approved workstation when handling the probe.
Input signal dynamic range
The input signal dynamic range is bound by the maximum voltage difference between either the A and B input of the probe
tip and the probe tip ground reference that the probe can accept without distorting the signal. Outside of the input signal
dynamic range, gain compression will result in increased linearity error and clipping. The DC specifications of the probe are
valid only over the input signal dynamic range. The dynamic range is not a hard limit for signal distortion; probe tip input
voltages can slightly exceed the dynamic range limit if a slightly higher linearity error is determined to be acceptable.
The differential and common-mode dynamic ranges for TekFlex probe tips are derived from the single-ended dynamic
range. The maximum differential signal can be twice the single ended range since the A side can be at the positive dynamic
range limit and the B side can be at the negative dynamic range limit (or vice versa). The maximum common-mode signal is
the same as the single-ended dynamic range limits. With the probe tip A and B offset voltages both set to 0 V, the dynamic
range will be symmetrical around that 0 V level. In this case, the dynamic range can be considered to equal ±(dynamic
range ÷ 2). If the oscilloscope vertical scale factor is set high enough to display the full dynamic range, the oscilloscope will
momentarily add dynamic range limit annunciation lines. These dynamic range annunciation lines can be refreshed by
adjusting one of the vertical channel knobs, such as position or scale factor.
Theory of operation
TDP7700 Series TriMode™ Probes Technical Reference
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