Title:
ILLEGAL ACCESS PREVENTING METHOD
Document Type and Number:
Japanese Patent JP2004302845
Kind Code:
A
Abstract:
To provide an illegal access preventing method permitting a simple structure that is easily manufactured at low cost.
In this method, at least one resistance element for irreversibly selecting high impedance state or low impedance state is provided to an interface part or a peripheral circuit part inside an integrated circuit, and when at least one signal different from collation information and a standard previously configured inside the integrated circuit is received, the impedance of the resistance element is changed from the initial state, and access to the integrated circuit is partly or entirely irreversibly stopped.
Inventors:
HIRAI MASAHIKO
Application Number:
JP2003094813A
Publication Date:
October 28, 2004
Filing Date:
March 31, 2003
Export Citation:
Assignee:
CANON KK
International Classes:
G06F21/60; G06F21/75; G06F21/86; G06K19/073; H01L21/822; G06F12/14; H01L27/04; (IPC1-7): G06F12/14; G06K19/073; H01L21/822; H01L27/04
Attorney, Agent or Firm:
Keizo Nishiyama
Yuichi Uchio
Yuichi Uchio