A 14b 200KS/s $0.87mm^2$ 1.2mW 0.18um CMOS Algorithmic A/D Converter

14b 200KS/s $0.87mm^2$ 1.2mW 0.18um CMOS 알고리즈믹 A/D 변환기

  • Published : 2006.12.25

Abstract

This work presents a 14b 200KS/s $0.87mm^2$ 1.2mW 0.18um CMOS algorithmic A/D converter (ADC) for intelligent sensors control systems, battery-powered system applications simultaneously requiring high resolution, low power, and small area. The proposed algorithmic ADC not using a conventional sample-and-hold amplifier employs efficient switched-bias power-reduction techniques in analog circuits, a clock selective sampling-capacitor switching in the multiplying D/A converter, and ultra low-power on-chip current and voltage references to optimize sampling rate, resolution, power consumption, and chip area. The prototype ADC implemented in a 0.18um 1P6M CMOS process shows a measured DNL and INL of maximum 0.98LSB and 15.72LSB, respectively. The ADC demonstrates a maximum SNDR and SFDR of 54dB and 69dB, respectively, and a power consumption of 1.2mW at 200KS/s and 1.8V. The occupied active die area is $0.87mm^2$.

본 논문에서는 각종 지능형 센서, control system 및 battery-powered system 응용과 같이 고해상도, 저전력 및 소면적을 동시에 요구하는 시스템을 위한 14b 200KS/s $0.87mm^2$ 1.2mW 0.18um CMOS 알고리즈믹 A/D 변환기 (ADC)를 제안한다. 제안하는 ADC는 요구되는 해상도 및 속도 사양을 만족시키면서, 동시에 면적을 최소화하기 위해 입력단 샘플-앤-홀드 앰프를 전혀 사용하지 않는 알고리즈믹 구조를 채택하였으며, 전체 ADC의 전력소모를 최소화하기 위해 핵심 아날로그 회로 부분에는 향상된 스위치 기반의 바이어스 전력 최소화 기법을 제안하였고, multiplying D/A 변환기에는 클록 선택적인 샘플링 커패시터스위칭 기법을 적용하였다. 또한, 초저전력 온-칩 기준 전류 및 전압 발생기를 제안하여 전체 ADC의 전력소모를 최소화하였다. 제안하는 시제품 ADC는 0.18um 1P6M CMOS 공정으로 제작되었으며, 측정된 DNL 및 INL은 각각 최대 0.98LSB 및 15.72LSB 수준을 보인다. 또한, 200KS/s의 동작 속도에서 SNDR 및 SFDR이 각각 최대 54dB, 69dB이고, 전력 소모는 1.8V 전원 전압에서 1.2mW이며 제작된 ADC의 칩 면적은 $0.87mm^2$이다

Keywords

References

  1. http://focus.ti.com/lit/ds/symlink/tlc3541.pdf
  2. http://www.analog.com/UploadedFiles/Data_Sheets/395089145AD7942_0.pdf
  3. http://www.analog.com/UploadedFiles/Data_Sheets/8014811AD7946_prd.pdf
  4. J. C. Morizio et al, '14-bit 2.2-MS/s sigma-delta ADC's,' IEEE J Solid-State Circuits, vol. 35, no. 7, pp. 968-976, July 2000 https://doi.org/10.1109/4.848205
  5. R. Jiang and T. S. Fiez, 'A 14-bit ${\triangle}-{\sum}$ ADC with 8x OSR and 4-MHz conversion bandwidth in a 0.18-um CMOS process,' IEEE J Solid-State Circuits, vol. 39, no. 1, pp. 63-74, Jan. 2004 https://doi.org/10.1109/JSSC.2003.820877
  6. http://focus.ti.com/litJds/symlink/ads8320.pdf
  7. M. Rebeschini et al, 'A 16-b 160-kHz CMOS A/D converter using sigma-delta modulation,' IEEE J Solid-State Circuits, vol. 25, no. 2, pp. 431-440, April 1990 https://doi.org/10.1109/4.52167
  8. H. Neubauer, T. Desel, and H. Hauer, 'A successive approximation A/D converter with 16bit 200kS/s in 0.6um CMOS using self calibration and low power techniques,' in ICECS, Sept. 2001, pp. 859-862 https://doi.org/10.1109/ICECS.2001.957609
  9. http://www.analog.com/UploadedFiles/Data_Sheets/1021466012AD7687_0.pdf
  10. H. C. Choi, S. B. You, H. Y. Lee, H. J. Park, and J. W. Kim, 'A calibration-free 3V 16b 500kS/s 6mW 0.5mm2 ADC with 0.13um CMOS,' in Symp. VISI Circuits Dig. Tech Papers, June 2004, pp. 76-77
  11. H. Guo, D. M. Rector, and G. S. La Rue, 'A low-power 16-bit 500kS/s ADC,' in Microelectronics and Electron Devices, April 2005, pp. 84-87
  12. B. M. Min, P. Kim, D. Boisvert, and A. Aude, 'A 69mW 10b 80MS/s pipelined CMOS ADC,' in ISSCC Dig. Tech Papers, Feb. 2003, pp. 324-325 https://doi.org/10.1109/ISSCC.2003.1234318
  13. H. W. Kim, D. K Jeong, and W. C. Kim, 'A 30mW 8b 200MS/s pipelined CMOS ADC using a switched-opamp technique,' in ISSCC Dig. Tech Papers, Feb. 2005, pp. 284-285 https://doi.org/10.1109/ISSCC.2005.1493980
  14. D. Y. Chang and S. H. Lee, 'Design techniques for a low-power low-cost CMOS A/D converter,' IEEE J Solid-State Circuits, vol. 33, no. 8, pp. 1244-1248, Aug. 1998 https://doi.org/10.1109/4.705363
  15. B. L. Jeon and S. H. Lee, 'A 10b 50MHz 320m W CMOS A/D converter for video applications,' Transactions on Consumer Electronics, vol. 45, no. 1, pp. 252-258, Feb. 1999 https://doi.org/10.1109/30.754443
  16. Y. D. Jeon and S. H. Lee, 'Acquisition time minimisation techniques for high-speed analogue signal processing,' Electron Lett., vol 35, pp. 1990-1991, Nov. 1999 https://doi.org/10.1049/el:19991378
  17. S. M. Yoo, T. H. Oh, J. W. Moon, S. H. Lee, and U. K Moon, 'A 2.5V 10b 120MSample/s CMOS Pipelined ADC with high SFDR,' in Proc. CICC, May 2002, pp. 441-444
  18. Y. J. Cho and S. H. Lee, 'An 11b 70-MHz 1.2-mm2 49-mW 0.18-um CMOS ADC with on-chip current/voltage references,' IEEE Transactions on Circuit and Systems I, vol. 52, no. 10, pp. 1989-1995, Oct. 2005 https://doi.org/10.1109/TCSI.2005.853251