1. An Example of Fitting a Model to a Chip Transistor A small-signal model will be fitted to a transistor (chip) in this example. The bias point and four boundary lines will also be specified to define the allowable intrinsic load-line area on the I/V-plane. Small-signal models are used in MultiMatch to find the optimum power load for a transistor and also to calculate the output power obtainable from the transistor in a MultiMatch circuit.

2. The Settings Command should be used to set the correct Data, Working and Export Directories

3. The directories set

4. The File | Open Command is used to open a MultiMatch circuit file

5. The circuit file is selected

6. The schematic of the circuit opened

7. The FET Model Command is selected in the Analysis Menu

8. A name must be specified for the.s2p or the.spi S-parameter data file

9. The FHX04X.s2p data file will be opened

10. A MultiMatch Identifier must also be specified for the transistor

11. The Initialize command on the Intrinsic Page will be selected

12. The Y-parameters will be fitted by using a least-square error function

13. The frequency range can be changed by using the Modify Range Command

14. The S-parameters of the model (solid colors) are compared with the measured parameters (mixed color traces)

15. Bounds can be set on the element values before the model is optimized

16. The value of Rd is constrained here

17. Rs is constrained

18. The S-parameter fit will be optimized by using the L1 error function

19. The S-parameters of the model are compared with the measured parameters

20. The final values of the fitted intrinsic components

21. The dc operating point and the four boundary lines defining the intrinsic load-line area allowed on the I/V plane must be specified on this page

22. The bias point and the line parameters were specified for the FHX04X. The OK Command will be used to close the Wizard and to create the required model file.

23. The model has been fitted and can now be used in the circuit. This example will be terminated at this point.