An FFE TX with 3.8x eye improvement by automatic impedance adaptation for universal compatibility with arbitrary channel and RX impedances

Abstract

An FFE TX which automatically adapts impedance to arbitrary channel and RX impedances is proposed. Based on on-chip TDR monitoring, the TX impedance matching is adaptively relaxed without increasing reflection. In experiment, the proposed TX adapted to any combination of 35–75Ω channels and 30–200Ω RX impedances, achieving 3.8x eye improvement and the maximum data rate of 12Gb/s.