A 70-mW seventh-order filter with 7-50 MHz cutoff frequency and programmable boost and group delay equalization

A seventh-order phase equiripple continuous time filter implementing pulse shaping and noise filtering for partial response maximum likelihood (PRML) read channel applications is presented. The 7-50 MHz cutoff frequency, amount of boost, and group-delay slope are programmable via 7-b digital-to-analog converters (DAC's). At 50 MHz fc, power consumption is 70 mW and output swing for 1% distortion is more than 500 mVpp. The transconductance capacitance (Gm-C) filter is built in a 0.7-/spl mu/m 10-GHz BiCMOS technology.