I'm using an external ADC with I2C, because the signal I have is a differential signal. The ADC I'm using is a sigma-delta type (ADS1110) and I'll be sampling at 60 sps.
My aim was to take ONE reading/sample then compare that reading to a set value. If the reading is too high do one thing, if it's too low, do something else.
Now a little dicky bird told me that I need to sample at a very high rate to avoid errors. So a bit of Googling and I learn about aliasing and sampling at least 10 times the signal frequency, etc.
This is the thing. I'm measuring the voltage of an electric plasma jet stream (from a plasma cutter) so I'm not measuring a frequency. I'm measuring a DC voltage which has lots of switching noise on it.
Would anyone say I'm in the ballpark if I focus on low pass filtering of the signal. The signal is already attenuated and filtered via an LCR circuit, but it's not my circuit and I have no idea what its characteristics are. With a resistor network I'll be attenuating the signal further to about a max of 2v at full scale.
60 readings per second should be more than enough for me, but like I say I'm hoping to be able to take just one ADC reading/sample each time (not multiple readings and averaging). Would a low pass filter work in this situation.