Stability Analysis of 3rd Order Fully Differential Active-RC Filter

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Published: Jul 8, 2020
Keywords:
Stability Criterion Fully-differential Active-RC Filters Common-mode Analysis

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Chairat Upathamkuekool
Department of Teacher Training in Electrical Engineering, Faculty of Technical Education, King Mongkut’s University of Technology North Bangkok, Bangkok

Abstract

In this paper, the stability conditions of fully-differential active-RC filters are investigated. A simple stability criterion, which relates the values of common-mode transconductance and output conductance of the op-amp to the value of resistors employed in the filter are presented. This simple stability criterion was derived and its validity was confirmed by simulation results. The 3rd order FD low-pass active-RC filter with Chebyshev response was designed to have 1-MHz bandwidth and 0.5-dB ripple at CMOS 0.18 μm technology and op-amps employed in the designed filter are folded cascode type whose operating points are set at mid supply voltage level by a self-feedback control circuit composed of op-amp half circuit and a comparator. In stable case, transient responses have suitable sinusoidal waveforms while the output unstable case transient responses are destorted because the DC voltage of the circuit was forced to be close to the supply rail. This stability criterion can be used to help in the design process and trade-off of the FD active-RC filters to be more effective.

Article Details

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Vol. 30 No. 3 (2020): July-September, 2020
Section
Engineering Research Articles

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References

[1] A. Vasilopulos, G. Vitzilaios, G. Theodoratos, and Y. Papananos “A low power wideband reconfigurable integrated Active-RC Filter with 73dB SFDR” IEEE Journal of Solid-State Circuits, vol. 41, pp. 1997–2008, September, 2006.

[2] J. Rogin, I. Kouchev, G. Brenna, D. Tschopp, and Q. Huang, “A 1.5-V 45 mW direct conversion WCDMA receiver IC in 0.13-m CMOS,” IEEE Journal of Solid-State Circuits, vol. 38, no. 12, 2003.

[3] F. Ciciotti, M. De Matteis, and A. Baschirotto, “A 0.9V 75MHz 2.8mW 4th-order analog filter in CMOS-bulk 28nm technology” presented at IEEE International Symposium on Circuits and Systems (ISCAS), Baltimore, MD, USA, May. 28–31, 2017.

[4] C. Upathamkuekool, A. Jiraseree-amornkun, and J. Mahattanakul, “Ultra low-power low-voltage active-RC Filter Design with on-chip automatic tuning,” in Proceedings the 8th Electrical Engineering/ Electronics, Computer, Telecommunications and Information Technology (ECTI) Association of Thailand - Conference 2011, 2011, pp. 86–89 (in Thai).

[5] K. Trijpech, O. Wiriyanuruknakorn, and J. Mahattanakul, “Common-mode rejection ratio analysis of fully differential class AB two-stage op-amp with and without commonmode feedback circuit,” in Proceedings 7th International Conference on ASIC, 2007, pp. 557–560.

[6] B. Razavi, Design of Analog CMOS Integrated Design of Analog CMOS Integrated Circuit. McGraw- hill, 2001, pp. 314–326.

[7] D. Johns and K. Martin, Analog Integrated Circuit Design. John Wiley and Sons, Inc., 1997, pp. 242–288.

[8] F. Ciciotti, M. De Matteis, and A. Baschirotto, “A 0.9V 600MHz 4th-order analog filter with feedforward compensated OPAMP in CMOS 28nm” presented at the 13th Conference on Ph.D. Research in Microelectronics and Electronics (PRIME), Giardini Naxos, Italy, June 12–15, 2017.

[9] S. Chatterjee, Y. Tsividis, and P. Kinget, “0.5-V analog circuit techniques and their applications to ota and filter design,” IEEE Journal Solid-State Circuits, vol. 40, no. 12, pp. 2373–2387, 2005.

[10] P. Khumsat and A. Worapishet, A 0.5-V R-MOSFET- C filter design using subthreshold R-MOSFET resistors and OTAs with cross-forward common-mode cancellation technique,” IEEE Journal of Solid-State Circuits, vol. 47, no. 11, pp. 2751–2762, 2012.

[11] C. Upathamkuekool, A. Jiraseree-amornkun, and J. Mahattanakul, Ultra low-power lowvoltage active-rc filter design with on-chip automatic tuning,” presented at The 8th Electrical Engineering/ Electronics, Computer, Telecommunications and Information Technology (ECTI) Association of Thailand - Conference 2011, Khon Kaen, Thailand, 2011 (in Thai).

[12] S. Pokaiudom, Negative Feedback Circuits and Oscillators. Bangkok: Mahanakorn university of technology, 2006 (in Thai).

[13] C. Upathamkuekool and J. Mahattanakul, Stability analysis of fully-differential active-RC filters with common-mode feedback network,” presented at the 14th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology (ECTI-CON), Phuket, Thailand, 2017 (in Thai).

[14] A. Phillip, CMOS Analog Circuit Design. Oxford University Press, 2002, pp. 243–323.

[15] P. Gray, P. Hurst, S. Lewis and R. Meyer, Analysis and Design of analog Integrated Circuits. John Wiley & Sons Inc, Hoboken, 2010, pp. 404–470.