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I am trying to do a load pull simulation using ADS for push pull FET power amplifier .

First I used the ADS one tone palette to simulate one of the FET's: enter image description here Then I found the optimum input and output load for all different frequencies: enter image description here Then i doubled the impedance I found to move to balanced configuration and this is the impedance I used to match the PA: for example: 2*(3.93+j0.977)=7.86+j1.954

Question: Is there a direct load pull simulation for balanced FET's that the 2 FET's are connected together to one differential load and source?

Dan.

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    \$\begingroup\$ Your question appears to be about potential facilities in ADS and that rather confuses me given the two pictures in your question. This makes your question "unclear what you're asking" and potentially subject to closure. Maybe you can make things clearer? \$\endgroup\$ – Andy aka Jun 5 '17 at 12:58
  • \$\begingroup\$ Are you using the LoadPull design guide from ADS or are you making your own load pull? \$\endgroup\$ – S.s. Jun 5 '17 at 16:18
  • \$\begingroup\$ Yes I am using the LoadPull design guide. but the design guide only work on single FET and I need 2 FET's in balanced configuration \$\endgroup\$ – Dan Jun 6 '17 at 8:05
  • \$\begingroup\$ Is your question regarding whether to apply load pull to single transistor or both transistors \$\endgroup\$ – aparna Jun 23 at 12:26
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I think you need to use ideal baluns for that.

enter image description here

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  • \$\begingroup\$ Does this work for higher frequencies? \$\endgroup\$ – aparna Jun 23 at 13:29
  • \$\begingroup\$ I will try it thanks \$\endgroup\$ – Dan Jun 24 at 13:56
  • \$\begingroup\$ I've used ideal baluns above to provide a first-approach template to evaluate how the push-pull arrangement works. However, you'll need to replace them by the s-parameter file of your real-life balun later. Concerning the practical implementation, traditional (wired) baluns can work up to 1.2-1.5GHz. See e.g. minirf.com/pdf/transformers/MRFXF0035DS.pdf On the other hand, I'm aware that progress has been made in designing microwave push-pull amplifiers using transmission line baluns. See, for example, this thesis core.ac.uk/display/20075325 \$\endgroup\$ – Andrés Martínez Mera Jun 24 at 16:15
  • \$\begingroup\$ @Dan: I think you can also use TLINP4 instead of balun in ADS simulation. \$\endgroup\$ – aparna Jun 26 at 7:10
  • \$\begingroup\$ @Andrés Martínez Mera: Thank you for your answer and link for Thesis. \$\endgroup\$ – aparna Jun 26 at 7:18
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I think there is no ready ADS template for push pull type configuration. Either you need to use single ended template and double the impedance or design your own load pull setup for this type of configuration.

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