A CMOS Fifth-Order 400MHz Current-Mode LF Linear Phase Filter for Hard Disk Read Channels

摘要

A 400MHz CMOS fifth-order linear phase g{sub}m-c filter based on current-mode (CM) leapfrog (LF) structure is realized. The filter is implemented using a fully-differential linear operational transconductance amplifier (OTA) based on source degeneration topology. PSpice simulations in a standard TSMC 0.18μm CMOS process and with 2.5V power supply have shown that the cut-off frequency of the filter ranges from 330MHz to 450MHz and dynamic range is about 64dB. The group delay is approximately 4% over the whole tuning range and total power consumption is only 190mW at 400MHz cut-off frequency.