Inductor-less 6~18 GHz 7-Bit 28 dB Variable Attenuator Using 0.18 μm CMOS Technology

0.18 μm CMOS 기반 인덕터를 사용하지 않는 6~18 GHz 7-Bit 28 dB 가변 신호 감쇠기

Na, Yun-Sik;Lee, Sanghoon;Kim, Jaeduk;Lee, Wangyoung;Lee, Changhoon;Lee, Sungho;Seo, Munkyo;Lee, Sung Chul

  • Received : 2015.12.10
  • Accepted : 2016.01.13
  • Published : 2016.01.31


This paper presents a 6~18 GHz 7-bit digital-controlled attenuator. The proposed attenuator is based on switched-T architecture, but no inductor is used for minimum chip size. The designed attenuator was fabricated using $0.18{\mu}m$ CMOS process, and characterized using on-wafer testing setup. The resolution(minimum attenuation step) and the maximum attenuation range of the attenuator were measured to be 0.22 dB and 28 dB, respectively. The measured RMS attenuation error and the RMS phase error for 6~18 GHz were less than 0.26 dB and $3.2^{\circ}$, respectively. The reference state insertion loss was less than 12.4 dB at 6~18 GHz. The measured input and output return losses were better than 9.4 dB over all frequencies and attenuation states. The chip size is $0.11mm^2$ excluding pads.


CMOS;Switched-T Attenuator;Nmos Switch


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Supported by : 국방과학연구소