A 48-Port FCC-Compliant 10GBASE-T Transmitter With Mixed-Mode Adaptive Echo Canceller Ramin Farjad

Abstract

High density 48-port netw ork switches demand very power-efficient, small form-factor physical layer transceivers which comply with the transmit PSD and return loss require- ments, on the one hand, and meet the FCC Class-A speci fications on the other hand, while achieving better than 10E-12 BER. The presented 10GBASE-T transmitter and hybrid utilize a current-mirroring ampli fier with output rise-time control and high CMRR to perform a first-order linear and nonlinear echo cancellation while enabling the desig n of 48-port FCC compliant network switches. Experimental results over the 400-MHz band- width exhibit a worst case transmitter linearity of 57 dBc as well as worst case post-hybrid fundam ental and SFDR power of 18 and 70 dBc, respectively, across the 400-MHz frequency range of interest. The echo fundamental c omponent is further attenuated to 60 dB in the analog domain by an adaptive mixed-mode echo canceller. Implemented in a 40-nm CMOS technology, the transmitter plus hybrid consu mes 200 mW power and occupies 0.5 mm .