DE-EMPHASIS — RATIO AND LINK COMPARISON
Use device/protocol documentation for permitted settings and reference planes. This
worksheet is an experiment record, not a compliance procedure.
Interface/version / rate / lane / hardware / firmware:
Channel board, connectors, cable and length:
Transmitter setting / device sign convention / source section:
Amplitude convention: differential or single-ended; peak or peak-to-peak:
D = 20*log10(Vrepeated/Vtransition); inverse ratio = 10^(D/20)
Illustrative: -3 dB -> 0.70795; 400 mV -> 283.18 mV.
Illustrative: -6 dB -> 0.50119; 400 mV -> 200.47 mV.
Signed ideal sequence 0,1,1,1,0,0 (preceding bit 1): -400,+400,+283,+283,-400,-283 mV. This
omits finite transitions.
Measurement reference plane / probes / fixture / de-embedding model:
Receiver equalization: fixed / trained / adaptive; exact settings:
Test pattern / duration / tested bit count / error count:
Baseline setting / eye and error results / evidence filename:
Changed setting (one variable) / results / evidence filename:
Voltage/temperature/channel corners repeated:
Standard acceptance criterion and version:
Decision / remaining uncertainty / next investigation:
Zero observed errors in a short run does not establish an arbitrary low error rate.

Yenra | Updated September 10, 2026
Article and explanation: https://yenra.com/electr/de-emphasis.html

Source references (use exact equipment/material documents for actual work):
https://www.ti.com/lit/an/sprabc1/sprabc1.pdf
https://www.ti.com/tw/lit/gpn/tusb501-q1
https://blog.teledynelecroy.com/2018/06/the-effects-of-de-emphasis-on-eye.html
https://www.teledynelecroy.com/doc/using-lecroys-eyedoctorii