Title:
SEMICONDUCTOR INTEGRATED CIRCUIT AND DATA CARRIER MOUNTED WITH THE SAME
Document Type and Number:
Japanese Patent JP3748857
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a semiconductor integrated circuit which enables a contactless type IC card (contactless information medium), having the circuit inside with simple constitution, to be made small-sized, is fast and free of regularity, and can generate uniform unpredictable random number data.
SOLUTION: A counter composed of a logic circuit which measures the time from when the contactless IC card enters a communication area of a reader writer to when a command of the reader/writer is actually received is mounted and its value is used as a random number value to generate a random number which is completely uniform and free of periodicity each time the contactless IC card enters the reader/writer communication area.
Inventors:
Joji Nakane
Mitsuo Oya
Mitsuo Oya
Application Number:
JP2003002679A
Publication Date:
February 22, 2006
Filing Date:
January 09, 2003
Export Citation:
Assignee:
Matsushita Electric Industrial Co., Ltd
International Classes:
G06K19/10; G06F7/58; G06K19/07; G09C1/00; H04L9/32; (IPC1-7): G06K19/10; G06F7/58; G06K19/07; G09C1/00; H04L9/32
Domestic Patent References:
| JP63098027A | ||||
| JP8030752A | ||||
| JP2001126037A |
Attorney, Agent or Firm:
Takao Itagaki
Yoshihiro Morimoto
Yoshihiro Morimoto