A −86.88 dBc/Hz @1 MHz K-band fractional-N frequency synthesizer in 90-nm CMOS technology

IEICE Electronics Express

Wu Zhaobo¹  Wang Zhengchen¹  Wang Xinghua¹ 

[1] School of Information and Electronic, Beijing Institute of Technology, Beijing Silicon SoC Engineering Research Center

关键词: frequency synthesizer;    phase noise;    charge pump;    MMD;    retime technique;   

DOI  :  10.1587/elex.15.20171063

学科分类：电子、光学、磁材料

来源: Denshi Jouhou Tsuushin Gakkai

【 摘 要 】

Through 90-nm CMOS technology, a K-band fractional-N frequency synthesizer has been designed. This paper proposes a new analysis to evaluate the noise current of the charge pump in fractional-N frequency synthesizer. It also designs an improved charge pump (CP). In addition, it also presents the multi-modulus divider (MMD) by the retime technique. The measured phase noise achieves −93.5 dBc/Hz and −86.88 dBc/Hz for integer-N and fractional-N modes at 1 MHz offset, respectively. The in-band phase noise performance can be improved about 20 dB by the retime technique. −54.63 dBc and −50.7 dBc reference spurs are respectively revealed by the spectrum for integer-N and fractional-N modes.

【 授权许可】

CC BY