I'm making a voltmeter for household batteries, what resistor values should I use on the input? Answered
So I've made a voltmeter, a basic outline is it has a different amp as the input, this feeds into an ADC DCA feedback system to find the accurate value. It works fine as it is but the purpose of it is to find the voltage of household batteries. I have heard that for this I will need to use large input resistors on the difference amp so that the voltage measured is more accurate when the battery is near depletion or something like that. Is this true? If so could someone explain it to me or send me a link to somewhere that does because everything I've found so far seems to be vague. I link would be great regardless as I need to show evidence of what I've found.
Thanks in advance.