CCMRR Common to Common Mode Rejection Ratio

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Common-to-common Mode Rejection Ratio (CCMRR) is a parameter relevant to differential output amplifiers, indicating how much common mode signal at the input translates to the output. The discussion highlights confusion surrounding CCMRR, Differential Common Mode Rejection Ratio (DCMRR), and Common Differential Mode Rejection Ratio (CDMRR), particularly in the context of twisted differential pair cabling and jacks. Clear definitions and examples for these terms are lacking, prompting a request for technical explanations and testing methods. Resources provided include links to documents that elaborate on differential signaling and practical measurements of these ratios. Understanding these concepts is crucial for predicting signal integrity in differential signaling applications.
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I understand Common-mode rejection ratio. I do not however understand common-to-common Mode rejection or common to differential mode rejection or differential to common mode rejection. I am looking at this in regard to twisted differential pair cabling, specifically jacks. I can find the term here and there but no clear definitions or examples.
 
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CCMRR is basically the same as CMRR but it's for differential output amplifiers. This parameter let's you predict how much of the common mode signal at the input will be passed to the common mode signal at the output. For a description of differential output signaling you can review this.
http://www.latticesemi.com/lit/docs/appnotes/pac/an6019.pdf
 
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Thanks for the start. I am lookin for a technical answer though. I understand differential signaling and all. I just don't understand CCMRR the difference between DCMRR and CDMRR. Maybe someone could explain how you test for it. Any help would be appreciated.
 
icthyus said:
Maybe someone could explain how you test for it.
Here's a site where someone plays with balanced line drivers and makes measurments of CCMRR, CDMRR and DCMRR. He shows the formulas relating input and output common mode signals.
http://sound.westhost.com/balance.htm"
 
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