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An Energy Efficient $V_{pp}$ Generator using a Variable Pumping Clock Frequency for Mobile DRAM  

Kim, Kyu-Young (School of Electrical Eng., Korea University)
Lee, Doo-Chan (Dept. of Nano Semiconductor Eng., Korea University)
Park, Jong-Sun (School of Electrical Eng., Korea University)
Kim, Soo-Won (School of Electrical Eng., Korea University)
Publication Information
Journal of the Institute of Electronics Engineers of Korea SD / v.47, no.6, 2010 , pp. 13-21 More about this Journal
Abstract
A energy efficient $V_{pp}$ generator using a variable pumping frequency for mobile DRAM is presented in this paper. The proposed $V_{pp}$ generator exploits 3 stages of a cross-coupled charge pump for energy efficiency. Instead of using a fixed pumping frequency in the conventional $V_{pp}$ generator, our proposed $V_{pp}$ generator adopts a voltage-controlled oscillator and uses variable frequencies to reduce the ramp-up time. As a result, our $V_{pp}$ generator generates 3.0 V output voltage with 24.0-${\mu}s$ ramp-up time at 2 mA current load and 1 nF capacitor load with 1.2 V supply voltage. Experimental results show that the proposed $V_{pp}$ generator consumes around 26% less energy (1573 nJ $\rightarrow$ 1162 nJ) and reduces 29% less ramp-up time (33.7-${\mu}s$ $\rightarrow$ 24.0-${\mu}s$) compared to the conventional approach.
Keywords
$V_{pp}$ generator; charge pump; voltage controlled oscillator; mobile DRAM;
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1 R. Pelliconi, et al., "Power efficient charge pump in deep submicron standard CMOS technology," IEEE J. Solid-State Circuits, vol. 38, no. 6, pp. 1068-1071, Jun. 2003.   DOI   ScienceOn
2 G. -H. Lim, et al., "Charge pump design for TFT-LCD driver IC using stack-MIM capacitor," IEICE Trans. Electron., vol. E91-C, no. 6, pp. 928-935, Jun. 2008.   DOI   ScienceOn
3 M. -D. Ker, S. -L. Chen and C. -S. Tsai, "Design of charge pump circuit with consideration of gate-oxide reliability in low-voltage CMOS processes," IEEE J. Solid-State Circuits, vol. 41, no. 5, pp. 1100-1107, May 2006.   DOI   ScienceOn
4 T. Tanzawa and T. Tanaka, "A dynamic analysis of the Dickson charge pump circuit," IEEE J. Solid-State Circuits, vol. 32, no. 8, pp. 1231-1240, Aug. 1997.   DOI   ScienceOn
5 J. -Y. Lee, et al., "A regulated charge pump with small ripple voltage and fast start-up," IEEE J. Solid-State Circuits, vol. 41, no. 2, pp. 425-432, Feb. 2006.   DOI   ScienceOn
6 S. -I. Cho, et al., "Two-phase boosted voltage generator for low-voltage DRAMS," IEEE J. Solid-State Circuits, vol. 38, no. 10, pp. 1726-1729, Oct. 2003.   DOI   ScienceOn
7 J. M. Rabaey, A. Chandrakasan and B. Nikolic, Digital Integrated Circuits, 2nd edition, Prentice-Hall, 2005.
8 C. G. Hwang, "New paradigms in the silicon industry," in IEDM Tech. Dig., 2006, pp. 1-8.
9 K. Itoh, et al., "Memory at VLSI circuits symposium," IEEE J. Solid-State Circuits, vol. 43, no. 4, pp. 762-768, Apr. 2008.   DOI
10 C. C. Wang and J. C. Wu, "Efficiency improvement in charge-pump circuits," IEEE J. Solid-State Circuits, vol. 32, pp. 852-860, June 1997.   DOI   ScienceOn
11 J. F. Dickson, "On chip high voltage generation in NMOS integrated circuits using an improved voltage multiplier technique," IEEE J. Solid-State Circuits, vol. 11, no. 3, pp. 374-378, Jun. 1976.   DOI
12 J. -T. Wu and K. -L. Chang, "MOS charge pump for low-voltage operation," IEEE J. Solid-State Circuits, vol. 33, no. 4, pp. 592-597, Apr. 1998.   DOI   ScienceOn