Since I will probably never get measurements outside of the 1 V range, could I limit my sensing range to 1V / 1024 ~= .1 mV? If I could get a resolution of .1 mV, all of my sensing requirements would be met.
I need to do some A-to-D sampling of a signal that will range from 0 to 50mv. I have a few of the Gravitech I2C-ADC boards so I can do 12-bit resolution, but it seems like I'll be sampling way down in the extreme lower end of everything, even if I use a 1.1v reference. I'm wondering if it would be better to amplify my low signal up to a higher level and sample it there, or would amplifying it cause more noise and error?
And definitely read the relevant sections of The Art of Electronics.... If precision is important its vital to design the circuit correctly. You don't want to find you're just measuring the temperature of your electronics!However if absolute precision isn't important an op-amp stage with adjustable offset might be quite useful in boosting your signal. You mention a resolution of 100uV but don't say what the range of values is, nor if absolute v. relative precision is important.For serious applications I wouldn't recommend any Arduino board as they all connect analog ground to digital ground - this will lead to a variety of problems in precision measurement.
Hello, I'm in the planning stages of a sensor array that will include several heat flux transducers, pyranometers, pyrgeometers, and thermistors...
Did you notice that you responded to a 4 year old thread?
No.First, there is no 16-bit resolution option. The A/D converters are 10-bit converters, and you can maybe squeeze out some extra bits through averaging but they are not precision analog front ends and there are no noise specs. They also have a "typical" absolute accuracy of +/-2LSB's so even at a 1.1V voltage reference (one of the options) and 2^10=1024 steps, the theoretical resolution is 1.1V/1024=1.07mV but the uncertainty is +/-2.15mV in each measurement.