The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 29, 2008
Filed:
Apr. 17, 2003
Hiromi Matsuda, Kanagawa, JP;
Eiichiro Morinaga, Tokyo, JP;
Masao Tanaka, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
Disclosed is a key generator, which assures the security of a key by preventing a circuit designer and other persons from readily knowing the value of the key. Random number generator circuits (and so on) generate random numbers respectively in accordance with different clocks (CLK, CLK, CLK, and so on). An arithmetic circuit () operates on the random numbers generated from the random number generator circuits (and so on) to generate an N-bit random number RA as the output from a random number generator (). This N-bit random number is RA acquired via a key selector (), and latched into a key register () in accordance with an acquisition enable signal EN from a timing monitoring counter (), which is driven by a clock CLKA other than clocks CLK, CLK, CLK, and so on, to obtain a hardware key, which is a unique secret key.