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US7177888: Programmable random bit source


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


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

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Foreign Patent Documents

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Other Publications

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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