High-speed DACs with random multiple data-weighted averaging algorithm

Current-steering DACs have intrinsic high-speed characteristics and are commonly used in wideband communication systems. However, element mismatch will cause harmonic distortion and thus limits their performance. This paper proposes a new algorithm, Random Multiple Data-Weighted Averaging (RMDWA), to reduce harmonic distortion due to element mismatch. RMDWA can be used to eliminate harmonics to increase spurious-free dynamic range (SFDR) and multi-tone power ratio (MTPR). DAC cost can be reduced since larger mismatch and smaller device size are allowed. In addition, low-complexity digital circuit used to implement RMDWA algorithm is presented in this paper.