Differential 16 bit ADC CMRR

[PatrickD]

Hi Everyone

I have spent some time trying to discover the common mode rejection ratio of the Kinetis K series internal ADC configured in 16 bit differential mode and have ploughed through datasheets, reference manuals and application notes without success. I have also performed web searches with similar results. CMRR is surely a salient parameter for any differential device and one would expect this to be clearly stated somewhere as without this detail it is practically impossible to estimate the degree of immunity to external interfering signals. Would anyone be party to this information?

Regards

Patrick

[xiangjun_rong · Accepted solution]

Hi, Patrick,

In data sheet of Kinetis, we define the CMRR spec for AD, it is about 84dB, in other words, the effect is about 1/10000. I cut it from the data sheet of K60P144M120SF3.pdf.

BR

Xiangjun Rong