A Comparative Study of Direct Digital Frequency Synthesizer Architectures in 180nm CMOS

Direct Digital Frequency Synthesizer (DDFS) has long been perceived as a predominant solution for producing precise, variable frequency signals having very low distortion. The paper presents an epigrammatic and a comparative study of direct digital frequency synthesizers architectures. The direct digital frequency synthesizer presented are compared on the basis of two architectures namely, the read only memory (ROM) or look up table based architecture and the other co-ordinate rotation based digital computer that eliminates the usage of the large ROM based look up table. These architectures are compared in terms of the power utilization, SFDR, etc. A mixed signal ASIC designing approach is followed for the implementation approach