Understanding Channel Operating Margin (COM) for Signal Integrity Analysis
What is Channel Operating Margin (COM)? You might be more familiar with Channel Operating Margin (COM) as it relates to IEEE 802.3 and OIF-CEI standards that use Phase-Amplitude-Modulation. For example, PAM-4 encodes four symbols per unit interval (UI), whereas NRZ modulation encodes one symbol per UI. A key advantage of PAM is that deployed hardware and existing PCB technology bins can achieve higher data-throughput rates by enhancing the modulation capability of PHY designs in silicon. ...