Hi Rupesh,

There is one bit of caution you should be made aware of. Don't think that just because you go to a higher bit count that you're going to get the full resolution the mathematics would suggest. In other words, don't think that just because you go to a 16-bit ADC that you will get 16-bits or resolution (1 part in 65536 or 2^16). Do a search of the forum and you will find several good posts explaining the problems.

In the meantime, even if you assume full benefit of a 12-bit ADC, you still only get 250,000/4096 = 61 g. So you would be forced to go to a 16-bit ADC. If, then, you could achieve 13-bit realizable resolution, you would have 250,000 / 2^13 = 250,000 / 8192 = 30 g resolution. Unfortunately, I can't tell you how easy or difficult 13-bit resolution is to achieve. Do the search and see what others have said.

Now, it is important to recognise one more thing. Even if you achieve 50g resolution, that doesn't mean you will be able to measure 50 g on a scale with a full-scale of 250,000 g. As a rule you will have increased error at the extremes of the scale. So, if you really need to measure 50g, you need some way to change full-scale.

I would make one final suggestion. Revisit the requirment, at least to the extent that you confirm it's a real need and not just a number that someone tossed off the top of their head. Is it possible that your supervisor said 50g when he meant to say 50 kg? It's a possibility anyway.

Good luck.