Abstract
As technology advances, the process gradually updates, more and more circuits can be design in the same area,and the performance is getting better and better. With this scientific and technological progress, many people are willing to try to carry out large-scale system integrated in one chip design, but if they want to put the signal into a computer for analysis and processing, they must use the analog to digital converter. This paper introduces three different continuous approximation analog-digital converters, each have different purposes, and their advantages and disadvantages. Three different type continuous approximation analog to digital converter are synchronous single input, non-synchronous single input, non-synchronous differential input, are described. Which a UMC 0.18mm process, TSMC 65nm, the TSMC 65nm process tape out, and analyze its functionality and efficiency for different circuitry places.