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Design >> RF Design >> attenuator/passive mixer interface
https://designers-guide.org/forum/YaBB.pl?num=1294800727

Message started by kelly on Jan 11^th, 2011, 6:52pm

Title: attenuator/passive mixer interface
Post by kelly on Jan 11^th, 2011, 6:52pm

Hi,
So my passive mixer drives a on chip IF VGA and has a 5p cap at the output for filtering. Thus, my input impedance is complex from 1G to 4G . There is going to be a on chip attenuator before the passive mixer. My questions are

1. can the attenuator has a ZL that is not only differernt from Zin but also complex? If it can, does that make the attenuator design a lot more comlex?
2. Will my best approach still be trying to make the mixer Zin look like a real resistor? Is that possible with an capacitive load at the IF port and do this for pretty broad band?

I guess to sum up my questions, what's the best approach in dealing with the attenuator/passive mixer interface?

Thanks.