I am currently working on an experiment which needs at least 0.1mV to 1mV resolution in the output. I am using the program ADCmeter.
But even though the manual says 1.05microVolts resolution at PGA 1, I am not able to reproduce the same in the output with PGA as 1.
While viewing the output in Hyperterminal, I have made provision to also see the result of "ulADC1Result" i.e ADC output along with the Voltage, and here I see that only first 12 bits from MSB are constant at a particular voltage and the rest 20 bits are constantly changing. According to the manual only the first 6 bits are to be affected by the noise which is clearly not the case in mine.
One more thing I observed was that even though I vary the gain ADCMDE_PGA_G1 from 1 to 4, there is no effect on the output.
Why is that ?