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US7177888: Programmable random bit source

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Filing Information

Inventor(s) Steven E. Wells ·
Assignee(s) Intel Corporation ·
Attorney/Agent(s) Blakely, Sokoloff, Taylor & Zafman LLP ·
Primary Examiner Tan V. Mai ·
Application Number US10633096
Filing date 08/01/2003
Issue date 02/13/2007
Prior Publication Data
Predicted expiration date 05/29/2025
Patent term adjustment 667
U.S. Classifications 708/3  · 708/251  ·
International Classifications G06F102  · G06J100  ·
Kind CodeB2
13 Claims, 6 Drawings


Abstract

A method of producing a uniform duty cycle output from a random bit source. The method includes testing the duty cycle of said random bit source; varying the output voltage of a voltage source if the duty cycle is not substantially fifty percent; and iteratively altering the output voltage of the voltage source until said duty cycle is substantially fifty percent.

Independent Claims | See all claims (13)

  1. 1. A method comprising: testing a duty cycle of a random bit source; varying an output voltage of a voltage source if the duty cycle has not substantially reached a first threshold; and iteratively altering the output voltage of the voltage source until the duty cycle has not substantially reached the first threshold.
  2. 8. A random bit source comprising: a latch to produce a uniform duty cycle output; a component to test the duty cycle; and a programmable voltage source to vary an output voltage if the duty cycle has not substantially reached a first threshold and iteratively alter the output voltage until the duty cycle has not substantially reached the first threshold.

References Cited

U.S. Patent Documents

Document NumberAssigneesInventorsIssue/Pub Date
US3790768 PRAYFEL INC Chevaller et al. Feb 1974
US4578649 Motorola, Inc. Shupe Mar 1986
US4694412 Intel Corporation Domenik et al. Sep 1987
US4791594 Technology Inc. 64 Harney et al. Dec 1988
US4810975 Dallas Semiconductor Corp. Dias Mar 1989
US4855690 Dallas Semiconductor Corporation Dias Aug 1989
US4905176* International Business Machines Corporation Schulz Feb 1990
US5007087 Loral Aerospace Corp. Bernstein et al. Apr 1991
US5473692 Intel Corporation Davis Dec 1995
US5539828 Intel Corporation Davis Jul 1996
US5568552 Intel Corporation Davis Oct 1996
US5627775 Applied Computing Systems, Inc. Hong et al. May 1997
US5706218 Intel Corporation Hoffman Jan 1998
US5778070 Intel Corporation Mattison Jul 1998
US5781458 Transcrypt International, Inc. Gilley Jul 1998
US5805712 Intel Corporation Davis Sep 1998
US5828753 Intel Corporation Davis Oct 1998
US5835594 Intel Corporation Albrecht et al. Nov 1998
US5844925 Ericsson Inc. Dent Dec 1998
US5844986 Intel Corporation Davis Dec 1998
US6026016 Intel Corporation Gafken Feb 2000
US6061702 Intel Corporation Hoffman May 2000
US6065029* N*Able Technologies, Inc. Weiss May 2000
US6104811 Telcordia Technologies, Inc. Aiello et al. Aug 2000
US6195433 Certicom Corp. Vanstone et al. Feb 2001
US6209098 Intel Corporation Davis Mar 2001
US6762636* Cypress Semiconductor Corp. Khawshe Jul 2004

Foreign Patent Documents

Document NumberAssigneesInventorsIssue/Pub Date
DE4006251Apr 1991
WO200059153INTEL CORPORATIONOct 2000
WO200059153INTEL CORPORATIONJan 2001
* cited by examiner

Other Publications

Blum, M., “Independent Unbiased Coin Flips from a Correlated Biased Source—A Finite State Markov Chain,” Combinatorica, vol. 6, No. 2, pp. 97-108 (1986).
Chor, Benny, et al., “Unbiased Bits from Sources of Weak Randomness and Probabilistic Communication Complexity,” SIAM Journal on Computing, vol. 17, No. 2, pp. 230-261 (Apr. 1988).
Cooper, J. Arlin, Computer Security, pp. 2072-2086 (published prior to Mar. 31, 1999).
Fairfield, R.C., et al., “An LSI Random Number Generator (RNG),” published in Proceedings in Advances in Cryptology Conference on CRYPTO, pp. 203-215 (1984).
Gude, Michael, “Concept for a High Performance Random Number Generator Based on Physical Random Phenomena,” Frequenz, 39, pp. 187-190 (Jul./Aug. 1985).
Murry, Herschell F. “A General Approach for Generating Natural Random Variables,” IEEE Transactions on Computers, pp. 1210-1213 (Dec. 1970).
Santha, Miklos, et al., “Generating Quasi-Random Sequences from Slightly-Random Sources,” Proceedings of the 25th Annual Symposium on Foundations of Computer Science, pp. 434-440 (Oct. 24-26, 1984).
Santha, Miklos, et al., “Generating Quasi-random Sequences from Semi-random Sources,” Journal of Computer and System Sciences, vol. 33, No. 1, pp. 75-87 (Aug. 1986).
von Neumann, John, “Various Techniques Used in Connection With Random Digits,” Applied Mathematics Series, vol. 12, United States Department of Commerce, National Bureau of Standards, pp. 36-38 (Jun. 11, 1951).
Shift Registers, pp. 1725-1727 (published prior to Mar. 31, 1999).
U.S. Appl. No. 09/283,096, filed Mar. 31, 1999, entitled “Duty Cycle Corrector for a Random Number Generator”, by Steven E. Wells and David A. Ward.
Schneler, Bruce, Applied Cryptography, John Wiley & Sons, Inc., pp. vii-xiv and 369-395 (2nd Ed., 1996).

Referenced By

Document NumberAssigneeInventorsIssue/Pub Date
US7904494 International Business Machines Corporation Choongyeun Cho et al. Mar 2011

Patent Family

Document NumberAssigneeInventorsIssue/Pub Date
US20050027765 Steven Wells Feb 2005
US7177888 Intel Corporation Steven E. Wells Feb 2007