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RF Electronics Chapter 9: Impedance Matching of Power Amplifiers Page 310 2022, C. J. Kikkert, James Cook University, ISBN 978-0-6486803-9-0. The equations for the band pass T network are as follows: D D L X QR X 1 where R D + jX D is the device impedance Eqn. 9.16 L C R A X 2 Eqn. 9.17 A Q B X C 1 Eqn. 9.18 Where A and B and the minimum Q are as before: This network can only be used if R D < R L , since otherwise negative values for C 1 result. Important notes: 1 Some of the equations for the Pi network are different since the reactive parts of the device are handled in the equations presented here and in the global variables panel of the AWR DE files for figures 9.9 to 9.19, while they are not in included in AN267 [1]. 2 In these notes A and B are kept the same in these notes, while A and B are swapped and changed in AN267. 3 In AN267 the term A for the Bandpass T is wrong. AN267 uses: 1 1 ) 1 ( 2 267 L L D R B R Q R A Eqn. 9.19 That will not give a correct match, as can be verified by using AWR DE. The square root should be extended to cover the –1 term as shown in the expression for A in equation 9.10. Capacitive Impedance Transformer Figure 9.5. Capacitive Impedance Transformer matching network. The capacitive transformer is not included in AN267, but this network can be quite useful and give very realisable components in inter-stage matching networks. The network is thus used to match the output impedance of one transistor to the input impedance of another transistor. The circuit is related to the lowpass Pi network, except the ground and the input port are changed. For this network, the output impedance at port 2 is always larger than that at port 1. For a non-reactive device, the equations for the component values are the same as those for the Pi network, with the input impedance being the same (at port 1), but the reference RF Electronics: Design and Simulation 310 www.cadence.com/go/awr

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