new_guy
Junior Member
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Posts: 10
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Hi,
I'm doing a standalone LNA for testing. I know the testing equipment is 50 ohms based, currently through literature, I found 3 kinds of termination.
1) Spara Matching, match S22 to 50 ohms (my view: safest but would putting a matching network degrade the power gain by 50% or -3 dB, maximum power matching theory) 2) Putting a common drain buffer (my view: how to deemb the effect after measuring its Sparamaters???) 3) the LNA has a LC tank load, saw some literature, putting a dc blocking cap before the GSG bias tee (my view:LC tank resonates at my opearting freq leaving inductor's series resistor, even if from calculation i make the series resistance 50 ohms, how would putting a dc blocking cap match series resistor to 50 ohms of bias tee. The series cap would cause a anti-clockwise shift on the smith chart. Right???)
Hope it makes sense. Thanks for anyone's views.
Regards Newbie
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