A CMOS lOOMHz CONTINUOUS-TIME SEVENTH ORDER 0.05' EQUIRIPPLE LINEAR PHASE LEAPFROG MULTIPLE LOOP FEEDBACK G,-C FILTER

A novel lOOMHz CMOS G,-C seventh-order 0.05" equiripple linear phase low-pass multiple loop feedback (MLF) filter based on the Leapfrog (LF) topology is presented. The filter is implemented using a fully-differential linear, high performance operational transconductance amplifier (OTA) based on crosscoupled pairs. PSpice simulations in a standard TSMC 0.25pm CMOS process and with a single 5V power supply have shown that the cut-off frequency of the filter without and with gain boost ranges from 8-32MHz and 15-100MHz, respectively. With gain boost, total harmonic distortion (THD) for a differential input voltage Vld of 315mVpp at lMHz is less than -4OdB, dynamic range at 1% THD is over 55dl3, output noise with bandwidth 5OOMHz is only 3 0 0 ~ V ~ ~ , and power consumption is 322mW.