This paper presents an analysis of switched-capacitor filters. Before discussion on switched-capacitor filters, we introduce the fundamental framework and concept of the filter, gradually leading up to our main subject. It is interesting to use a high quality and high bandwidth AD-811 to connect the switched-capacitor filters, and then proceed to find the differences between the original and equivalent circuit by a spectrum analyzer. This paper provides a fundamental structure for switched-capacitor filter researches, so that future studies may be built upon it.