IC CARD DEVICE AND RECEIVER USING THE SAME

摘要

PURPOSE:To completely protect secret information by providing a RAM for storing the secret information and an auxiliary power source for the RAM in the IC card device and further providing a means which stops supplying electric power to said RAM when an illegal action is taken. CONSTITUTION:The receiver 200 uses the IC card device 230 and broadcast data are divided by a division part 210 into secret data 250 and sent data 260. The secret data 250 is sent the IC card device 230 with a key parameter. A control part 232 deciphers a key parameter for descrambling the sent data 260 by using the key parameter and the master key of a key storage part 234. A descrambling part descrambles the sent data 260 with the key parameters 270 and outputted the resulting data finally. The RAM stored with the secret information for key deciphering and the power source are connected by a lead line laid around in the IC card device 100 and when this RAM is taken out, the lead wire is broken.