niloufar-navidi
Junior Member level 1
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Hi everyone,
When we want to calculate ADCs sampling capacitor size we choose C such that thermal noise level is less (or equal) than quantization noise
KT/C<Δ2/12
Which leads to
C>12KT×22b/VFS2
My question is that if "C" here is the total capacitance of the capacitor array or unit cell capacitor? and why?
For example if in the case of an eight bit ADC we find C>20fF from C>12KT×22b/VFS2
should we divide 20fF by 28 to find the minimum unit cell size or C is the minimum unit cell size itself?
When we want to calculate ADCs sampling capacitor size we choose C such that thermal noise level is less (or equal) than quantization noise
KT/C<Δ2/12
Which leads to
C>12KT×22b/VFS2
My question is that if "C" here is the total capacitance of the capacitor array or unit cell capacitor? and why?
For example if in the case of an eight bit ADC we find C>20fF from C>12KT×22b/VFS2
should we divide 20fF by 28 to find the minimum unit cell size or C is the minimum unit cell size itself?