A Digitally-Assisted Electrothermal Frequency-Locked Loop in Standard CMOS

  • S. Mahdi Kashmiri
  • Kofi A. A. Makinwa
Part of the Analog Circuits and Signal Processing book series (ACSP)


This chapter describes an electrothermal frequency-locked loop (FLL) that is suitable for CMOS integration. An electrothermal FLL requires a narrow noise-bandwidth to limit the jitter resulting from the thermal noise of its electrothermal filter (ETF). This is rather challenging to implement in the analog domain, since the narrow bandwidth requires the realization of a large time constant. This chapter proposes a digitally-assisted FLL (DAFLL) architecture that mitigates the integration difficulties of previous FLLs. In the DAFLL, the narrow-band loop filter is realized in the digital domain. As such, it does not require off-chip analog components. Initially, the proposed system-level architecture will be introduced. Later, the design, implementation and characterization of the major building blocks will be covered. These include a phase digitizer realized by means of a phase-domain ΔΣ modulator (PDΔΣM), and a digitally-controlled oscillator (DCO).


Digital Filter Phase Reference Test Chip Synchronous Demodulator Digital Integrator 
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  1. 1.
    Murmann B (2006) Digitally assisted analog circuits. IEEE Micro 26(2):38–47CrossRefGoogle Scholar
  2. 2.
    Staszewski RB, Balsara PT (2006) All-digital frequency synthesizer in deep-submicron CMOS. Wiley, HobokenCrossRefGoogle Scholar
  3. 3.
    Makinwa KAA, Snoeij MF (2006) A CMOS temperature-to-frequency converter with an inaccuracy of less than ±0.5 °C (3σ) from −40 °C to 105 °C. IEEE J Solid-State Circ 41(12):2992–2997CrossRefGoogle Scholar
  4. 4.
    Kashmiri SM, Makinwa KAA (2009) A digitally-assisted electrothermal frequency-locked loop. In: Proceedings of the 35th ESSCIRC, Athens, Greece, pp 296–299Google Scholar
  5. 5.
    Schreier R, Temes GC (2005) Understanding delta-sigma data converters. Wiley, Hoboken/ChichesterGoogle Scholar
  6. 6.
    Breems LJ, Huijsing JH (2001) Continuous time sigma delta modulation for A/D conversion in radio receivers. Kluwer Academic Publishers, Dordrecht, The Netherlands, SpringerGoogle Scholar
  7. 7.
    Kashmiri SM et al (2009) A temperature-to-digital converter based on an optimized electrothermal filter. IEEE J Solid-State Circ 44(7):2026–2035CrossRefGoogle Scholar
  8. 8.
    van Vroonhoven CPL, Makinwa KAA (2008) A CMOS temperature-to-digital converter with an inaccuracy of ±0.5 °C (3σ) from −55 to 125 °C. In: IEEE ISSCC Dig. Tech. Papers, San Francisco, CA, February 2008, pp 576–577Google Scholar
  9. 9.
    van Vroonhoven CPL et al (2010) A thermal-diffusivity-based temperature sensor with an untrimmed inaccuracy of ±0.2 °C (3σ) from −55 °C to 125 °C. In: IEEE ISSCC Dig. Tech. Papers, San Francisco, CA, pp 314–315Google Scholar
  10. 10.
    Huijsing JH (2001) Operational amplifiers theory and design. Kluwer, Boston. ISBN 0-7923-7284-0Google Scholar
  11. 11.
    Feely O, Chua LO (1991) The effect of integrator leak in Σ-Δ modulation. IEEE Trans Circuit Syst 38(11):1293–1305zbMATHCrossRefGoogle Scholar
  12. 12.
    Denison T et al (2007) A 2 μW 100 nV/rtHz chopper-stabilized instrumentation amplifier for chronic measurement of neural field potentials. IEEE J Solid-State Circ 42(12):2934–2945CrossRefGoogle Scholar
  13. 13.
    Sanduleanu M et al (1998) A low noise, low residual offset, chopped amplifier for mixed level applications. In: Proceedings of the IEEE international conference on electronics, circuits and systems, Lisboa, Portugal, vol 2, pp 333–336Google Scholar
  14. 14.
    Witte JF, Makinwa KAA, Huijsing JH (2007) A CMOS chopper offset-stabilized opamp. IEEE J Solid-State Circ 42(7):1529–1535CrossRefGoogle Scholar
  15. 15.
    Bult K, Geelen GJGM (1990) A fast-settling CMOS op amp for SC circuits with 90-dB DC gain. IEEE J Solid-State Circ 25(6):1379–1384CrossRefGoogle Scholar
  16. 16.
    Yun Chiu I, Gray PR, Nikolic B (2004) A 14-b 12-MS/s CMOS pipeline ADC with over 100-dB SFDR. IEEE J Solid-State Circ 39(12):2139–2151CrossRefGoogle Scholar
  17. 17.
    Bakker A, Huijsing JH (1996) Micropower CMOS temperature sensor with digital output. IEEE J Solid-State Circ 31(7):933–937CrossRefGoogle Scholar
  18. 18.
    Razavi B (2001) Design of analog CMOS integrated circuits. McGraw-Hill, New YorkGoogle Scholar
  19. 19.
    Staszewski RB et al (2005) A digitally controlled oscillator in a 90 nm digital CMOS process for mobile phones. IEEE J Solid-State Circ 40(11):2203–2211CrossRefGoogle Scholar
  20. 20.
    Gardner FM (1980) Charge-pump phase-locked loops. IEEE Trans Commun 28:1849–1858CrossRefGoogle Scholar
  21. 21.
    Sun SY (1989) An analog PLL-based clock and data recovery circuit with high input jitter tolerance. IEEE J Solid-State Circ 24(2):325–330CrossRefGoogle Scholar
  22. 22.
    Abidi AA, Meyer RG (1983) Noise in relaxation oscillators. IEEE J Solid-State Circ 18(6):794–802CrossRefGoogle Scholar
  23. 23.
    Gierkink SLJ, van Tuijl Ed (AJM) (2002) A coupled sawtooth oscillator combining low jitter with high control linearity. IEEE J Solid State Circuits 37(6):702–710Google Scholar
  24. 24.
    Schoeff JA (1979) An inherently monotonic 12 bit DAC. IEEE J Solid-State Circ 14(6):904–911CrossRefGoogle Scholar
  25. 25.
    van den Bosch A et al (2001) A 12 b 500 MSample/s current-steering CMOS D/A converter. In: IEEE ISSCC Dig. Tech. Papers, San Francisco, CA, pp 366–367Google Scholar
  26. 26.
    Zhang C, Makinwa KAA (2008) Interface electronics for a CMOS electrothermal frequency-locked-loop. IEEE J Solid-State Circ 43(7):1603–1608CrossRefGoogle Scholar
  27. 27.
    Kashmiri SM, Makinwa KAA (2009) Measuring the thermal diffusivity of CMOS chips. In: Proceedings of the IEEE sensors, Christchurch, New Zealand, pp 45–48Google Scholar
  28. 28.
    Hamann HF et al (2007) Hotspot-limited microprocessors: direct temperature and power distribution measurements. IEEE J Solid-State Circ 42(1):56–65CrossRefGoogle Scholar
  29. 29.
    Vermeersch B (2009) Thermal AC modelling, simulation and experimental analysis of microelectronic structures including nanoscale and high-speed effects. Ph.D. dissertation, University of GentGoogle Scholar
  30. 30.
    Touloukian YS et al (1998) Thermophysical properties of matter, vol 10. Plenum, New YorkGoogle Scholar
  31. 31.
    McConnell AD, Goodson KE (2005) Thermal conduction in silicon micro- and nanostructures. Annu Rev Heat Trans 14:129–168CrossRefGoogle Scholar
  32. 32.
    Ebrahimi J (1970) Thermal diffusivity measurement of small silicon chips. J Phys D Appl 3:236–239CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • S. Mahdi Kashmiri
    • 1
  • Kofi A. A. Makinwa
    • 2
  1. 1.Texas Instruments, Inc.DelftThe Netherlands
  2. 2.Delft University of TechnologyDelftThe Netherlands

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