Intel 1000BASE-T User Manual

100BASE-TX Waveform Overshoot
1000BASE-T/100BASE-TX/10BASE-T Physical Layer Compliance Tests Manual
38 Intel Confidential
Figure 9-3. Positive Peak Waveform with No Overshoot on the Rising Edge
5. Calculate the overshoot by measuring the number of millivolts that the rising edge exceeds the
positive or negative peak voltage (measured in Section 8) and dividing the measured overshoot
voltage by the corresponding peak voltage. Multiply the result by 100 to obtain the percentage.
6. Record the results.
7. Select the paired-dot cursors. Move one cursor to the zero voltage crossing and the other
cursor to 8 ns beyond the first cursor position.
The overshoot voltage shall have decayed to within 1% of the steady state voltage within 8 ns
following the beginning of the differential signal transition.
8. Repeat steps 3 through 7 using Table 9-2 to measure negative overshoot.
Figure 9-4. Calculating Overshoot
9. Verify the measurements meet specifications
If the negative peak voltage (the voltage delta between the MLT-3 mid-level and the
negative pulse top) is -1000 mV and the overshoot voltage is 35 mV, then the percentage
overshoot is:
%
35mV
1000mV
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100× 3.5=

Intel 1000BASE-T Specifications

General

Brand	Intel
Model	1000BASE-T
Category	Adapter
Language	English