hi,
I am doing small project and would like design AC voltmeter with range 0 ... 300V with resolution of 0.1V. I need a help how to design the analog front end. On the net are many digital voltmeter diy circuits but usually only digital part Nobody solve the analog part?
That's easy. Use a standard AD converter you like. Maybe 7107 or 7135 or a MCU with ADC. At input you need to make a Precision full-wave AC/DC converter (two OpAmps). At input to precision full-wave AC/DC converter you need a resistor divider.