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A Loop Filter Size and Spur Reduced PLL with Two-Input Voltage Controlled Oscillator

두 개의 입력을 가진 VCO를 이용하여 루프필터와 스퍼 크기를 줄인 위상고정루프

  • Choi, Young-Shig (Department of Electronic Engineering, Pukyong National University) ;
  • Moon, Dae-Hyun (Department of Electronic Engineering, Pukyong National University)
  • Received : 2018.05.03
  • Accepted : 2018.06.04
  • Published : 2018.08.31

Abstract

In this paper, a novel PLL has been proposed that reduces the size of the loop filter while suppressing spur by using a VCO with two inputs. Through the stability analysis according to the operating status, the PLL is designed to operate stably after the phase fixing. The capacitor of loop filter usually occupies larger area of PLL. It is a VCO that can reduce the size of the loop filter by increasing the effective capacitance of the capacitor through the simultaneous charge and discharge operation by two charge pumps and has two signals operating in opposite phases. The settling time of set to $80{\mu}s$ approximately by using a LSI(Locking Status Indicator) indicating the phase locking status. The proposed PLL is designed using a supply voltage of 1.8V and a $0.18{\mu}m$ CMOS process.

본 논문에서는 위상고정 상태에 따라 활성화 되는 루프가 다르게 설정하고, 두 개의 입력을 가지는 전압제어발진기를 사용하여 스퍼를 억제함과 동시에 루프필터의 크기를 줄이는 위상고정루프를 제안하였다. 동작 상태에 따른 안정도 분석을 통하여 위상고정 후에는 위상고정루프가 안정적으로 동작되게 설계하였다. 일반적으로 루프 필터의 커패시터는 위상고정루프에서 큰 면적을 차지한다. 두 개의 전하펌프에 의한 동시 충 방전 동작을 통해 커패시터의 유효커패시턴스를 증가시켜 루프필터 크기를 줄일 수 있으며, 서로 반대 위상으로 동작하는 두 개의 신호를 입력으로 가지는 전압제어발진기로 스퍼의 크기를 억제할 수 있었다. 위상고정 상태를 알려주는 LSI(Locking Status Indicator)를 사용하여 위상고정 시간은 $80{\mu}s$가 되도록 하였다. 제안된 위상고정루프는 1.8V의 공급전압과 $0.18{\mu}m$ CMOS공정을 사용하여 설계하였다.

Keywords

References

  1. K Praveen Kumar, "Estimation of traffic management and road safety", Asia-pacific Journal of Convergent Research Interchange, vol.3, no. 2, pp. 21-28, Jun. 2017. https://doi.org/10.21742/APJCRI.2017.06.03
  2. C. R Ho, and M. S. W. Chen, "A digital pll with feedforward multi-tone spur cancelation loop achieving <-73dBc fractional spur and <-100dBc reference spur in 65nm CMOS," Institute of electrical and electornics engineers journal of Solid-State Circuits, vol. 51, no. 12, pp. 3216-3230, Dec. 2016.
  3. H. J. Kim and Y. S. Choi, "Electron spectroscopy studies on magneto-optical media and plastic substrate interfaces," Institute of Electronics Engineers of Korea Semiconductor and Devices, vol. 53, no. 4, pp. 136-141, Apr. 2016.
  4. Y. Tang, M. Ismail and S. Bibyk, "Adaptive miller capacitor multiplier for compact on-chip PLL filter," Electronics Letters, vol. 39, no. 1, pp. 43-45, Jul. 2003. https://doi.org/10.1049/el:20030086
  5. I.-C. Hwang, "Area efficient and self-biased capacitor multiplier for on-chip loop filter," Electronics Letters, vol. 42, no. 24, pp. 1392-1393, Nov. 2006. https://doi.org/10.1049/el:20062486
  6. J. Choi, J. Pakr, W. kim and J. Laskar, "High multiplication factor capacitor multipier for an on -chip PLL loop filter," Electronics Letters, vol. 45, no. 5, pp. 239-240, Feb. 2009. https://doi.org/10.1049/el:20092874
  7. Z. Zhang, J. Yang, L. Liu, P. Feng, J. Liu, and N. Wu, "Source-switched charge pump with reverse leakage compensation technique for spur reduction of wideband PLL," Electronics Letters, vol. 52, no. 14, pp. 1211-1212, Jul. 2016. https://doi.org/10.1049/el.2016.1036
  8. C. Y. Yang and S. I. Liu, "Fast-swtiched frequency synthesizer with a discriminator-aided phase detector," Institute of electrical and electronics engineers journal Solid state, vol. 35, no. 10, pp. 1445-1452, Oct. 2000.
  9. Y. S. Choi and S. J. Ahn, "Design of dual loop PLL with low noise characteristic," Journal of the Korean Institute of Information Communication Engineering, vol. 20, no. 4, pp. 819-825, Apr. 2016. https://doi.org/10.6109/jkiice.2016.20.4.819