طراحي يك فيلتر آنتي الايزينگ ويديو با پهناي باند قابل تنظيم با استفاده از خازنهاي متغيرگيت MOS

In this paper, an analog Low pass GmIC filter with tunable cutoff frequency from 1.5 to 5.5 MHZ is designed. This filter is used in adjustable - bandwidth antialiasing video filters. Cut off frequency tuning is done using depletion - mode substrate - biased MOS gate capacitors. A fifth order elliptic filter is designed by cascade synthesis method. The filter consists of a first order and two notch Biquadratic fully differential Gm/C sections. The cutoff frequency of each section can be tuned independently by substrate bias voltage of Mos gate capacitors. The Hspice simulation results show the efficiency of this tuning method for tunable video filters.