A 2-GHz Direct Digital Frequency Synthesizer Based on LUT and Rotation

This paper proposes a direct digital frequency synthesizer (DDFS) based on Lookup-Table-Rotation (LUT-ROT) architecture. The DDFS takes the advantages of coarse-fine LUT and pipelined rotation units to achieve both high-speed and high-resolution. Based on the analysis of approximation error, the trade-off between accuracy and memory usage is achieved, which leads to the lowest amplitude of noise and the smallest size of LUT. Experimental results show that the DDFS achieves 11.7mW/GHz power consumption and 96dBc SFDR in 2-GHz clock frequency.