Patent · US Expired

Random number generation using back electromotive force (BEMF) values

US7330328B2 · kind B2 · utility

8Cited by
13References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 17, 2006
Grant dateFeb 12, 2008
Priority date
Expiry dateFeb 17, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F7/588
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Method and apparatus for generating a random number, such as for use in a security protocol to control access to a data processing system. A processor generates the random number in relation to a back electromotive force (BEMF) value. The BEMF value is preferably obtained in response to application of current to a circuit. The circuit preferably comprises a coil and the application of current preferably induces a relatively small movement of the coil. The random number is preferably a multi-bit digital value, and each bit of the random number is determined in relation to whether the corresponding BEMF value is even or odd. The coil preferably comprises a coil of a voice coil motor (VCM) used to position a transducer adjacent a rotatable storage medium, and the random number is preferably generated while the medium is in a non-rotatable state.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.