A simple question regarding blocking capacitors - RF Cafe Forums

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Post subject: A simple question regarding blocking capacitors

Unread postPosted: Mon Jul 05, 2004 1:07 pm

during SpectreRF simulation, how much value should be assigned to the blocking capacitors on the input and output ports? Say, if I let the capacitor on the input be 1pF, then I can get one result, but if I change it to 1nF, the result will be another story. How to decide the proper values to use? Thanks

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Buding

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Unread postPosted: Tue Jul 06, 2004 9:27 am

What frequency are You using. In simulation You can put as high capacitance as You wich. Just to achieve blocking effect. In real life You have to take into account other thing like resonaces, losses, parsitics and many more.

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Buding

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Unread postPosted: Tue Jul 06, 2004 9:29 am

What frequency are You using. In simulation You can put as high capacitance as You wich. Just to achieve blocking effect. In real life You have to take into account other thing like resonaces, losses, parsitics and many more.

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DW

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Unread postPosted: Sun Jul 11, 2004 6:35 pm

another way to think about blocking capacitors is as single pole high pass filters. You want your response to be well into the passband if at all possible.

BR,

DW

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Jeanalmira

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Unread postPosted: Tue Mar 15, 2005 5:25 am

hi,

just want to add that should be careful in using large capacitance values for blocking cap, as higher capacitance values, has lower resonance frequency, so that it might be inductance instead at frequency higher than f resonance :wink:

Regards,

Jean

Posted  11/12/2012