Design of a 6 Gbps Continuous-Time Adaptive Equalizer Using a Voltage Rectifier Instead of a Power Detector

Krishna Srinivasan and Jonathan Rosenfeld
Intel Corporation


Abstract

This paper presents the advantages of using a power detector over a voltage rectifier in the design of an adaptive equalizer. Two types of voltage rectifiers, CMOS based and diode based, are compared for potential application in an adaptive equalizer feedback loop. The CMOS rectifier, however, works only at lower frequencies and is limited by the maximum rectification frequency. Instead, voltage rectification in an adaptive equalizer is demonstrated by simulation using an ideal Schottky diode. These designs have been compared by simulation against published work on negative feedback adaptive equalization using a CMOS power detector. The advantages of using a power detector is ease of implementation and higher bandwidth of operation compared to the design using a CMOS voltage rectifier.