Design of a Low-Pass Switched Capacitor Fourth Order Chebyshev Filter Using an Improved Auto Zero Integrator
Subject Areas : electrical and computer engineering
Mohammad
Rashtian
1
O.
Hashemipour
2
K.
Navi
3
Keywords: Auto zeroed integratorhigh-speedlow voltage switched capacitor circuitcommon mode feedback,
Abstract :
In this work the low-voltage high-speed auto zeroed integrator characteristics is improved by utilizing the non-linear properties of switches. Based on this improvement a newly designed structure for a low-pass filter is presented. The designed filter is a fourth order Chebyshev with pass band frequency of 500 KHz and sampling frequency of 5 MHz. Based on this method a fast and accurate sample and hold structure is introduced. The designed work is simulated using 0.25µm CMOS technology at 1.2 V supply voltage.
[1] J. T. Wu, Y. H. Chang, and H. L. Chang, "1.2-V CMOS switched-capacitor circuits," in IEEE int. Solid-State Circuit Dig. Tech. Papers, pp. 388-389, Feb. 1996.
[2] E. Kume, et al., "An experimental 1.5 V 64 Mb DRAM," IEEE J. Solid-State Circuits, vol. 26, no. 4, pp. 465-472, Apr. 1992.
[3] J. Sauerbrey, T. Tille, D. Schmitt-Landsiedel, and R. Thewes, "A 0.7-V MOSFET-only switched-opamp ∑Δ modulator in standard digital CMOS technology," IEEE J. Solid-State Circuits, vol. 37, no. 12, pp. 1662-1669, Dec. 2002.
[4] A. Baschirotto and R. Castello, "A 1-V 1.8-MHz CMOS switched-opamp SC filter with rail-to-rail output swing," in IEEE Int. Solid-State Circuits Dig. Tech. Papers, pp. 58-59, Feb. 1997.
[5] F. Krummenacher, "Micropower switched capacitor biquadratic cell," IEEE J. Solid-State Circuits, vol. 17, no. 3, pp. 507-512, Jun. 1982.
[6] L. Wang and S. H. K. Embabi, "Low-voltage high-speed switched-capacitor circuits without voltage bootstrapper," IEEE J. Solid-State Circuits, vol. 38, no. 8, pp. 1411- 1415, Aug. 2003.
[7] M. Rashtian and O. Hashemipour, "An improved low-voltage high speed switched capacitor circuit," Presented at 14th Iranian Conf. on Electrical Engineering, ICEE 2006, Tehran, Iran, 2006.
[8] P. E. A. Douglas and R. Holbrg, CMOS Analog Circuit Design, 2nd Edition, 2003.