Derivation of Loop Gain and Stability Test for Low-pass Tow-Thomas Biquad Filter
MinhTri Tran, Anna Kuwana, Haruo Kobayashi · 2020
Proposed derivation and measurement of self-loop function for a low-pass Tow Thomas biquadratic filter are introduced.The self-loop function of this filter is derived and analyzed based on the widened superposition principle.The alternating current conservation technique is proposed to measure the self-loop function.Research results show that the selected passive components (resistors, capacitors) of the frequency compensation of Miller's capacitors in the operational amplifier and the Tow Thomas filter can cause a damped oscillation noise when the stable conditions for the transfer functions of these networks are not satisfied.