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Design >> Analog Design >> question about power analysis
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Message started by tulip on Dec 16^th, 2015, 6:33pm

Title: question about power analysis
Post by tulip on Dec 16^th, 2015, 6:33pm

In Razavi’s book <RF microelectronics>(second edition), it says “ For a sinusoidal input voltage with an rms value of Vin, the power delivered to the input port is equal to Vin²/Re[Zin]”

My question is : if the input impedance of the port is Zin=A+jB, after some calculations, I get a different result, as shown in the attachment. I do not know which one is correct. Would you please read the attachment and see which one is correct.

Thank you very much.

Title: Re: question about power analysis
Post by raja.cedt on Dec 17^th, 2015, 6:50am

That has been stated under the assumption of matched load or pure resistive load.

Title: Re: question about power analysis
Post by tulip on Dec 22^nd, 2015, 4:47am

I see, thank you.

raja.cedt wrote on Dec 17^th, 2015, 6:50am:

That has been stated under the assumption of matched load or pure resistive load.