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Measurements >> RF Measurements >> How to find the DCoffset in the simulation
https://designers-guide.org/forum/YaBB.pl?num=1177230342

Message started by James Bond on Apr 22^nd, 2007, 1:25am

Title: How to find the DCoffset in the simulation
Post by James Bond on Apr 22^nd, 2007, 1:25am

Hi, all

I am designing a direct convertion double balanced active mixer, followed by a dc-offset cacellation circuit. I set 5% mismatch in the load resistors.I seached some articles on the website, they said they have less 300uV dc offset after applying the dc-offset cancellation circuit, but I don't know how to find the dc-offset of the ouput.

I also searched this forum, someone said use pss analysis, I have tried , but before plot the curve, one needs to choose what kind of curve they need to plot, the most possiblity is Voltage plot, but it shows the dc voltage of the output node(possitive, negative IF) which is 1.3V in my design. I am really confused about how to find the dc offset, please , if someone knows where I am wrong, please don't hesitate to point out. Thank you very much.

Best Regards
Bond James

Title: Re: How to find the DCoffset in the simulation
Post by augjan on Jun 27^th, 2007, 5:51pm

Mybe you can cut off the feedback circuit at first to simulate DC and gain the delt voltage of the outputs of mixer(with R mismatch), then simulate all system to find the delt Vout of the mixer