The CD41AD49QF of 14-bit A/D Converter ( Analog-to-Digital Converter) with sampling rates up to 250MSPS is monolithic integrated circuits manufactured using CMOS Technology，this Converter has characteristics of high speed and high precision. A new design approach is taken advantage in this A/D Converter to achieve high dynamic performance as well as ultralow-power at 1.8V supply. It is can be used for multi-carrier broadband communication application. The elementary diagram of A/D Converter. This circuit include pipelining processing, out driver circuit, internal generation reference circuit, Clock duty cycle stabilizer, control logic and digital Correction circuit. This circuits are available in a compact QFN-48 package and can alternative similar products of ADS4149 made by Texas Instrument (TI).