Voltage Differencing Gain Amplifier-Based Shadow Filter: A Comparison Study
Pitchayanin Moonmuang, Tattaya Pukkalanun, Worapong Tangsrirat
Abstract
This study determines the voltage-mode shadow filter realization based on voltage differencing gain amplifier (VDGA) in comparison with a classical second-order filter. The realized shadow filter uses three VDGAs and only two grounded capacitors, and can simultaneously realize second-order lowpass and bandpass filter responses. The natural angular frequency (ω <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">A</sub> ) and the quality factor (Q <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">A</sub> ) can be tuned by means of the VDGAs' transconductance gains. The performance comparison between the realized shadow filter and the classical second-order filter is demonstrated through simulation results with 0.25μm CMOS technology.