ADC Resolution vs ENOB

Thread Starter

hoyyoth

Joined Mar 21, 2020
287
Hello,


We know that ADC 1LSB=Vref/(2^N) where N is the resolution of the ADC.

We know that ADC Effective number of bits (ENOB) is always less than the resolution "N".

When calculating 1LSB do I need to take 1LSB = Vref/(2^ENOB) or I need to take 1LSB=Vref/(2^N)
 

drjohsmith

Joined Dec 13, 2021
813
Hello,


We know that ADC 1LSB=Vref/(2^N) where N is the resolution of the ADC.

We know that ADC Effective number of bits (ENOB) is always less than the resolution "N".

When calculating 1LSB do I need to take 1LSB = Vref/(2^ENOB) or I need to take 1LSB=Vref/(2^N)
The difference between ENOB and true bits, is expressed as "noise"
so for an 8 bit DAC you always have 8 bits, but the bottom two bits might be "noise"
but then if you average 16 samples of the same "voltage" , then you regain the two bits, ..
https://www.ti.com/lit/pdf/sprad55#...conversions,how much oversampling takes place.
 

Thread Starter

hoyyoth

Joined Mar 21, 2020
287
The difference between ENOB and true bits, is expressed as "noise"
so for an 8 bit DAC you always have 8 bits, but the bottom two bits might be "noise"
but then if you average 16 samples of the same "voltage" , then you regain the two bits, ..
https://www.ti.com/lit/pdf/sprad55#:~:text=Software oversampling performs multiple conversions,how much oversampling takes place.
Thank you.
" bottom two bits might be "noise" ".
Bottom two bits means LSB.Please correct me if I am wrong
 
Top