20-GHz quadrature injection-locked LC dividers with enhanced locking range

Takayuki Shibasaki, Hirotaka Tamura, Kouichi Kanda, Hisakatsu Yamaguchi, Junji Ogawa, Tadahiro Kuroda

Research output: Contribution to journalArticle

25 Citations (Scopus)


Quadrature injection-locked LC dividers with either a Miller topology or an injection-locked LC VCO topology are coupled with transconductors to enhance their locking range. The effect of the transconductance coupling is analyzed theoretically and through circuit simulation. Both topologies were fabricated by 90-nm CMOS technology with a target input center frequency of 20 GHz and output frequency of 10 GHz. The measured locking range for the Miller topology with transconductance coupling is 25.3%, compared to 20.9% without coupling. The measured locking range for the injection-locked LC VCO topology with transconductance coupling is 18.1%, compared to 12.9% without coupling. Moreover, power consumption for both dividers is 6.4 mW with a 1.2-V supply.

Original languageEnglish
Article number4456788
Pages (from-to)610-618
Number of pages9
JournalIEEE Journal of Solid-State Circuits
Issue number3
Publication statusPublished - 2008 Mar 1



  • Frequency dividers
  • Injection locking
  • Miller divider
  • Quadrature
  • Voltage-controlled oscillators (VCO)

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

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