Title :
Edge and Data Adaptive Equalization of Serial-Link Transceivers
Author :
Wong, Koon-Lun Jackie ; Chen, E-Hung ; Yang, Chih-Kong Ken
Author_Institution :
Broadcom Corp., Irvine, CA
Abstract :
Limited channel bandwidth introduces inter-symbol interference (ISI) at both data and edge samples. In addition to the ISI at data samples, ISI at the edge samples (edge ISI) increases the bit error rate (BER) by degrading on the eye diagram and increasing the jitter of the clock and data recovery (CDR). This work proposes a forward FIR equalizer and a decision-feedback equalizer (DFE) that compensate for both data and edge samples. To adapt both the data and edge equalizers, a modified LMS adaptation algorithm is introduced to achieve convergence. A transmitter and receiver are implemented in 0.13 mum and 0.18 mum technologies respectively. The edge ISI is improved by 20% and the jitter is improved by 10% in measurement. The link operates over a 120´´ FR4 channel with 24 dB attenuation at Nyquist frequency, and the BER is below 10-14 at 3.6 Gb/s.
Keywords :
FIR filters; adaptive equalisers; compensation; convergence of numerical methods; decision feedback equalisers; error statistics; intersymbol interference; least mean squares methods; timing jitter; transceivers; BER; FR4 channel; Nyquist frequency; bit error rate; channel bandwidth limitation; clock and data recovery; convergence aspects; data adaptive equalization; decision-feedback equalizer; edge ISI; edge samples; eye diagram; forward FIR equalizer; inter-symbol interference; jitter; modified LMS adaptation algorithm; on-chip data processing; serial-link transceivers; size 0.13 mum; size 0.18 mum; size 120 in; Adaptive equalizers; Bandwidth; Bit error rate; Clocks; Decision feedback equalizers; Degradation; Intersymbol interference; Jitter; Signal analysis; Transceivers; Bit-error rate; CDR; I/O link; ISI; LMS adaptation; equalizer;
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.2008.2001876
