The design of active filters using the in-line pole approximation

A synthesis is presented which has enabled a practical switchable filter to be realized which will give an optimum linear phase response together with satisfactory amplitude and transient response using a computed in-line pole distribution. Theoretical and practical characteristics are compared for a fourth- and sixth-order filter and the appropriate circuit diagrams are given. The application of this type of filter is discussed with particular reference to the field of medical electronics.