I have a certain analog signal v(t) which varies from 0 to 2V, which I want to be read by Arduino.
I know that Arduino can read it through the function
AnalogRead, and the result will be a sequence of numbers from 0 to 1023. Now, I have some doubts:
The input range 0 - 5V is mapped to 0 - 1023. Therefore, if I get the result X and I want to find the original input voltage V, I have to apply the formula: V = X * 5 V /1023. Correct?
The output range is 0 - 1023: this means that Arduino uses 10 bit for the A/D conversion. If I am correct, this means that the Arduino resolution is equal to 5V/1024 = 4.88 mV. But my signal varies from 0 to 2V, so there is a waste of bits. I think the conversion might be better. For instance, if all 10 bits were used for the range 0 - 2V, we would get a resolution of 2V/1024 = 2mV. Any solution? Moreover, what does it happen if I decide to amplify my voltage with a gain = 2.5? Is there a benefit?