Optimal design of Voltage-controlled Voltage Source second-order unit gain Butterworth low-pass filter

Reports a method of design low-pass filter. Based on analyzing the error isogram of the Voltage-controlled Voltage Source(VCVS) 2nd-order Low-pass filter´s parametric equation by MathCAD, the paper put forward that VCVS unit gain Butterworth fO Hz Low-pass filter optimal design plan: firstly, select two capacitances C1 and C2, making C2/C1 0.5; and then calculate value of two resistances by the same expression 0.2251/(f0C1). Obviously, the design plan has the advantages of convenience, low-cost and easy compensation of temperature drift. And with the aid of Multisim-10, MathCAD and real circuit experiment the design plan has also been verified its advantage of stability. In addition, the analysises also indicate that ensure the parametric accuracy of C2 and R2 is more important than that of C1 and R1.