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AD8331  Adding LC Bandpass filter between LNAout and VGAin?

Question asked by BruceLong on Jun 3, 2016
Latest reply on Mar 7, 2018 by CNR

The data sheet application and test circuits show the AD8331 LNA amplifier externally coupled to the VGA section with the use of two dc blocking capacitors.   Is there any obvious reason why the broad band coupling capacitors could not be replaced with - for sake of example - a two pole, 10% bandwidth LC bandpass filter designed for 200 Ohms Zin and Zout assuming the DC block is maintained and good RF layout practice and component placement?

 

Note:  the VGA input impedance is specified in the data sheet as 200 Ohms

 

Thanks   Bruce

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