Title:
IC CARD
Document Type and Number:
Japanese Patent JP2004199249
Kind Code:
A
Abstract:
To make it difficult to analyze current consumption without lengthening an actual processing time in a contact type IC card to which a power is supplied from the outside.
An IC card 21 is provided with a random number generator as a power supply current control circuit 24 and a breeder circuit for making current flow based on random numbers generated by the random number generator. Thus, it is difficult to analyze the change of the actual current consumption of an IC card logic part 10 because of current by the random number generation circuit from power supply current, and the privacy of the IC card 21 is protected. Since current is changed by random numbers, and it is not necessary to lengthen an actual processing time.
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Inventors:
NANBU KEIICHI
Application Number:
JP2002365089A
Publication Date:
July 15, 2004
Filing Date:
December 17, 2002
Export Citation:
Assignee:
MATSUSHITA ELECTRIC IND CO LTD
International Classes:
G06F12/14; G06F21/55; G06F21/62; G06F21/75; G06F21/86; G06K19/073; (IPC1-7): G06K19/073; G06F12/14
Attorney, Agent or Firm:
Masaaki
Ohashi
Masanori Hirano
Hayashi Hiroki
Ohashi
Masanori Hirano
Hayashi Hiroki