Using an amplifier to increase resolution of a turbidity sensor

Support Arduino
1

Hi,
I’m trying to use one of these turbidity sensors to look at turbidity in seawater, but the resolution from the ADC on the arduino units I’m using is too low. Could you tell me how much of an affect adding one of these will have: amplifiers?

For reference I found the resolution low when starting to play with it and home, and others have done the calculations and found it’s resolution is in steps of 7.25 NTU, where seawater in normal circumstances ranges up to 22 NTU.
Thanks

2

Hey Dean,

I know we solved this one already over our support line, but I’ll just pop a bit of info up here for anyone else who checks on the topic!

An ADC’s resolution effect can be determined with a quick bit of maths.If you have a 5V signal and a 10-bit ADC (like the specs you’d find on an Arduino’s analogue GPIO pins), you would have a resolution of 5/(2^10) or 5/1024 which is around 4.88mV.

If you were to implement a 16-bit ADC with the same 5V signal, it would be 5/(2^16) or 5/65536 which is around 0.07mV for the resolution (much more accurate steps).

I’m not super familiar with those turbidity units, so someone else might be able to tag in to help out, but the 16-bit ADC should definitely help a bit with giving a better resolution on the reading!