ABSTRACT
This chapter discusses design information for passive RLC filters, including Butterworth, Thomson, and Chebyshev, both singly and doubly terminated. As the filter slope is increased in order to obtain greater rejection of frequencies beyond cut-off, the complexity and cost are increased and the response to a step input is worsened. In particular, the overshoot and the settling time are increased. The most common function in signal processing is the Butterworth. It is a function that has only poles and has the flattest magnitude possible in the passband. This function is also called maximally flat magnitude. The Thomson function is one in which the time delay of the network is made maximally flat. This implies a linear phase characteristic since the steady-state time delay is the negative of the derivative of the phase. This function has excellent time-domain characteristics and is used wherever excellent step response is required.
