Apart from the mentioned monotonocity ( hope the spelling is OK )the basic issue is " How do you guarantee the conversions or in other words calibrate the setup ? "

Even with a regular ADC from a major like Analog Devices or BurrBrown, one is not sure whether he is getting the specified resolution and precision - these are highly influenced by the PCB layout, Vref stability and other hardware issues. That being the case how does one go about with a home brewed ADC ?

I generally thought that R-2R type home built convertor is for student projects - just to drive in the concept where calibartion is mostly a non issue.


Raghu