Design of MIC Broadband Loads and Attenuators

Design tables for broadband terminations are presented. The termination circuits consist of one or two ¿/4 transmission lines in cascade loaded with a resistance in series with an open circuit stub. Since no holes in the substrate or metallic connections with the groundplanes are needed the design is suitable for printed circuits. Measurements have been made on a termination which had a total length of ¿/2. The bandwidth was designed to be 85 percent. The experimental result is close to the theoretical predictions. Broadband terminations of this kind may be used in a number of ways. An example of a broadband modified Pi-attenuator without a ground connection is included.