PROTECTING SECRET INFORMATION IN A PROGRAMMED ELECTRONIC DEVICE

摘要

The invention concerns a technique for protecting secret information (34) in a programmed electronic device, the programmed electronic device comprising a non-trusted memory (46) containing software (48), a data memory (32) containing the secret information (34), and an access restriction logic unit (36) that is adapted to allow or block access to the secret information (34), the secret information (34) being adapted to be used for verifying the integrity of the software (48). When starting up the programmed electronic device, the access restriction logic unit (36) allows access to the secret information (34). Then the secret information (34) is accessed for use in verifying the integrity of the software (48), and subsequently the access restriction logic unit (36) blocks further access to the secret information (34). A semiconductor device and a programmed electronic device comprise similar features. The invention provides a way for securely protecting secret information - for example, a secret key - in a programmed electronic device.