you go with analog.com (they provide samples for amny countries ) or similar makers of 16 bits adc (and more ) then any 8 bit micro (but you have not mentioned the sampling rate - that could be a big constraint) and may be sd or mmc card to things within nonvolatile. There are ready to use libraries for MMC for different micros and adc connection should not be a problem but layout must be done properly to get all 16 bits. Pay attention to signal conditioning before ADC as it must provide performance for 16 bit aquisition .
BTW analog has nice application documents concerning subject .
Hi tae
-What I need is a ready-made on-shelf product.
-About the sampling rate, in my case the sampled signal is within the voice band.
-Can you please post the link for the analog application document?