A Novel Fully-Differential Gm-C Filter Structure for Communication Channel Equalizer

In this paper, a novel Gm-C filter for equalizers used in communication channels transmitting digital data for applications in CMOS integrated circuits is presented. Using the novel structure the poles of internal Gm-blocks are avoided and better stability and ability to operate in high frequencies are achieved. To tune the filter, instead of changing transconductance (Gm), we have used variation of capacitance (C). Cat5 data cable is used for testing and simulating the circuit. The design has been processed in a 0.3 5 mum four-metal single-poly CMOS process. Power consumption of the chip is 18mW and the area is 53000mum2 which are both improved in comparison to previous conventional designs.

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