i am using adc for current signal measurement. controller frequency is 8MHz and i initialise adc as
1] prescaler-> 64
2] adc interrupt-> enable
3]adc reference ->internal 1.1v
4]auto triggering of adc ->enable
5]auto trigger source -> free running mode.
i have considered 200ms time span samples, sqaure it , average it and then take square root
why for fixed current input adc count vary 2 to 3 count?