Derivation of Loop Gain and Stability Test for Multiple Feedback Low-pass Filter Using Deboo Integrator

A new stability test for a multiple feedback low pass filter using Deboo integrator is described. The loop gain of this filter is derived and analyzed based on the widened superposition principle. The voltage injection technique is used to measure this loop gain. Test results show that the feedback loops in this filter may cause damped oscillation noises when the stable conditions are not satisfied.