Is a 1-lsb white noise amplitude critical in ADC input?

[Regnum]

Questions about ADCs

In a MCU built-in A/D converter, may I get an extra-bit resolution using a 4x oversampling frequency, and averaging the four intermediate results supposing there's over 1-lsb white noise at the A/D input ? Is this noise amplitude critical somehow?

Should I rather think of using an external converter?

Thanks

 

[xirix]

Re: Questions about ADCs

You should obtain 1-bit extra resolution at 4x oversampling and filtering.
The general rule is 1/2LSB at 2x oversampling.

 

[eda4you]

Re: Questions about ADCs

For the assumption of white quantization noise to be constant over the band of interest. If not there will be no benefit!