Capacitance Reduction Technique for Switched-Capacitor Circuits Based on Charge Distribution and Partial Charge Transfer

This paper proposes a technique to reduce the capacitance spread in switched-capacitor (SC) filters. The proposed technique is based on a simple charge distribution and partial charge transfer which is applicable to various integrator topologies. An implementation example on an existing integrator topology and a design example of a 2nd-order SC low-pass filter are given to demonstrate the performance of the proposed technique. A design example of an SC filter show that the filter designed using the proposed technique has an approximately 23% less total capacitance than the one of SC low-pass filter with conventional capacitance spread reduction technique.

[1]  Wonchan Kim,et al.  A 1 . 5V , 4-MHz CMOS Continuous-Time Filter with a Single-Integrator Based Tuning , 1998 .

[2]  Eitake Ibaragi,et al.  A 1-MHz 7th-order continuous-time lowpass filter using very low distortion CMOS OTAs , 2000, 2000 IEEE International Symposium on Circuits and Systems. Emerging Technologies for the 21st Century. Proceedings (IEEE Cat No.00CH36353).

[3]  Armin Tajalli,et al.  A low-power CMOS Gm-C filter for wireless receiver applications with on-chip automatic tuning system , 2006, 2006 IEEE International Symposium on Circuits and Systems.

[4]  W.M.C. Sansen,et al.  An area-efficient approach to the design of very-large time constants in switched-capacitor integrators , 1984, IEEE Journal of Solid-State Circuits.

[5]  M. Banu,et al.  Fully integrated active RC filters in MOS technology , 1983, 1983 IEEE International Solid-State Circuits Conference. Digest of Technical Papers.

[6]  Shigetaka Takagi,et al.  Capacitance spread reduction technique for low-cost switched-capacitor filters implementation , 2009, 2009 European Conference on Circuit Theory and Design.

[7]  Hyun-Kyu Yu,et al.  A 1.8V triode-type transconductor and its application to a 10MHz 3/sup rd/-order Chebyshev low pass filter , 2004, Proceedings of the IEEE 2004 Custom Integrated Circuits Conference (IEEE Cat. No.04CH37571).

[8]  Sunki Min,et al.  3.3-V baseband Gm-C filters for wireless transceiver applications , 2003, Proceedings of the 2003 International Symposium on Circuits and Systems, 2003. ISCAS '03..

[9]  Sanjit K. Mitra,et al.  Extremely low sensitivity active RC filter , 1969 .

[10]  B. Hoefflinger,et al.  MOS switched-capacitor filters with reduced number of operational amplifiers , 1979, IEEE Journal of Solid-State Circuits.

[11]  P. Landau,et al.  A reduced capacitor spread algorithm for elliptic bandpass SC filters , 1987 .

[12]  Mohammed Ismail,et al.  Low-voltage CMOS GM-C filter with rail-to-rail common-mode voltage , 1996, Proceedings of the 39th Midwest Symposium on Circuits and Systems.

[13]  Mohammed Ismail,et al.  A low-voltage, low-power CMOS fifth-order elliptic GM-C filter for baseband mobile, wireless communication , 1997, IEEE Trans. Circuits Syst. Video Technol..

[14]  Mohammed Ismail,et al.  Low-voltage, micropower weak-inversion CMOS GM-C filter , 1996, Proceedings of Third International Conference on Electronics, Circuits, and Systems.

[15]  Changsik Yoo,et al.  A /spl plusmn/1.5-V, 4-MHz CMOS continuous-time filter with a single-integrator based tuning , 1998 .

[16]  Mi-Young Lee,et al.  A 1.2V, 10MHz, low-pass Gm-C filter with Gm-cells based on triode-biased MOS and passive resistor in 0.13/spl mu/m CMOS technology , 2005, Proceedings of the IEEE 2005 Custom Integrated Circuits Conference, 2005..

[17]  Kenneth R. Laker,et al.  Synthesis of a low-sensitivity multiloop feedback active RC filter , 1974 .

[18]  Chorng-Kuang Wang,et al.  A scalable high-performance switched-capacitor filter , 1986 .

[19]  J. G. Linvill,et al.  RC Active Filters , 1954, Proceedings of the IRE.

[20]  A. Yasuda,et al.  A 2.7-V, 200-kHz, 49-dBm, stopband-IIP3, low-noise, fully balanced gm-C filter IC , 1999 .

[21]  J. H. Fischer.  Noise sources and calculation techniques for switched capacitor filters , 1982 .