DOI QR코드

DOI QR Code

Low-Voltage Tunable Pseudo-Differential Transconductor with High Linearity

  • Received : 2009.02.18
  • Accepted : 2009.08.12
  • Published : 2009.10.31

Abstract

A novel tunable transconductor is presented. Input transistors operate in the triode region to achieve programmable voltage-to-current conversion. These transistors are kept in the triode region by a novel negative feedback loop which features simplicity, low voltage requirements, and high output resistance. A linearity analysis is carried out which demonstrates how the proposed transconductance tuning scheme leads to high linearity in a wide transconductance range. Measurement results for a 0.5 ${\mu}m$ CMOS implementation of the transconductor show a transconductance tuning range of more than a decade (15 ${\mu}A/V$ to 165 ${\mu}A/V$) and a total harmonic distortion of -67 dB at 1 MHz for an input of 1 Vpp and a supply voltage of 1.8 V.

Keywords

References

  1. S. Koziel and S. Szczepanski, “Design of Highly Linear Tunable CMOS OTA for Continuous-Time Filters,” IEEE Trans. Circuits and Systems II, vol. 49, no. 2, Feb. 2002, pp. 110-122. https://doi.org/10.1109/TCSII.2002.1002513
  2. B. Calvo et al., “Low-Voltage Linearly Tunable CMOS Transconductor with Common-Mode Feedforward,” IEEE Trans. Circuits and Systems I, vol. 55, no. 3, Apr. 2008, pp. 715-721. https://doi.org/10.1109/TCSI.2008.919746
  3. G. Bollati et al., “An Eighth-Order CMOS Low-Pass Filter with 30-120 MHz Tuning Range and Programmable Boost,” IEEE J. Solid-State Circuits, vol. 36, no. 7, July 2001, pp. 1056-1066. https://doi.org/10.1109/4.933461
  4. U. Chilakapati, T. Fiez, and A. Eshraghi, “A CMOS Transconductor with 80-dB SFDR up to 10 MHz,” IEEE J. Solid-State Circuit, vol. 37, Mar. 2002, pp. 365-370. https://doi.org/10.1109/4.987089
  5. W. Huang and E. Sánchez-Sinencio, “Robust Highly Linear High-Frequency CMOS OTA with IM3 below -70 dB at 26 MHz,” IEEE Trans. Circuits and Systems I, vol. 53, no. 7, July 2006, pp. 1433-1447. https://doi.org/10.1109/TCSI.2006.875187
  6. I. Mehr and D.R. Welland, “A CMOS Continuous-Time Gm-C Filter for PRML Read Channel Applications at 150 Mb/s and Beyond,” IEEE J. Solid-State Circuits, vol. 32, no. 4, Apr. 1997, pp. 499-513. https://doi.org/10.1109/4.563671
  7. M. Shaker, S.A. Mahmoud, and A.M. Soliman, “New CMOS Fully-Differential Transconductor and Application to a Fully Differential Gm-C Filter,” ETRI Journal, vol. 28, no. 2, Apr. 2006, pp. 175-181. https://doi.org/10.4218/etrij.06.0105.0173
  8. A. Lopez-Martin et al., “CMOS Transconductors with Continuous Tuning Using FGMOS Balanced Output Current Scaling,” IEEE J. Solid-State Circuit, vol. 43, no. 5, May 2008, pp. 1313-1323. https://doi.org/10.1109/JSSC.2008.920333
  9. C. Lujan-Martinez et al., “A Tunable Pseudo-Differential OTA with −78 dB THD Consuming 1.25 mW,” IEEE Trans. Circuits and Systems II, vol. 55, no. 6, June 2008, pp. 527-531. https://doi.org/10.1109/TCSII.2007.916757
  10. A. Torralba et al., “Low-Voltage Transconductor with High Linearity and Large Bandwidth,” Electronics Letters, vol. 38, no. 25, Dec. 2002, pp. 1616-1617. https://doi.org/10.1049/el:20021172
  11. A. Zeki, “Low-Voltage CMOS Triode Transconductor with Wide-Range and Linear Tunability,” Electronics Letters, vol. 35, no. 20, Sept. 1999, pp. 1685-1686. https://doi.org/10.1049/el:19991167
  12. R.G. Carvajal et al., “The Flipped Voltage Follower: A Useful Cell for Low-Voltage Low-Power Circuit Design,” IEEE Trans. Circuits and Systems I, vol. 52, no. 7, July 2005, pp. 1276-1291. https://doi.org/10.1109/TCSI.2005.851387
  13. A. Baschirotto, F. Rezzi, and R. Castello, “Low-Voltage Balanced Transconductor with High Input Common-Mode Rejection,” Electronics Letters, vol. 30, no. 20, Sept. 1994, pp. 1669-1671. https://doi.org/10.1049/el:19941163
  14. G. Palumbo and S. Pennisi, “High-Frequency Harmonic Distortion in Feedback Amplifiers: Analysis and Applications,” IEEE Trans. Circuits and Systems I, vol. 50, no. 3, Mar. 2003, pp. 328-340. https://doi.org/10.1109/TCSI.2003.808835
  15. S.O. Cannizzaro, G. Palumbo, and S. Pennisi, “Distortion Analysis of Miller-Compensated Three-Stage Amplifiers,” IEEE Trans. Circuits and Systems I, vol. 53, no. 5, May 2006, pp. 961-976.

Cited by

  1. A CMOS inverter-based class-AB pseudo-differential amplifier with current-mode common-mode feedback (CMFB) vol.74, pp.2, 2009, https://doi.org/10.1007/s10470-012-9970-0
  2. Pseudo-Differential Transconductor Circuit for a Low Supply Voltage Application vol.1962, pp.1, 2009, https://doi.org/10.1088/1742-6596/1962/1/012015