Method and apparatus for increasing security in a system using an integrated circuit
AssigneeFreescale Semiconductor, Inc.
InventorsThomas E. Tkacik, Asaf Ashkenazi
Life of this patent
Estimating the term…
Abstract
An integrated circuit can be made more secure by programming a one time programmable circuit so that different signals are provided on terminals as compared to when the integrated circuit was not secure. Instead, or in addition, the integrated circuit can be made more secure by providing decode circuitry that can be used with the one time programmable circuit to select different internal address maps in response to an address value. The decode circuitry can use a first address map when the integrated circuit is secure, and a different address map when the integrated circuit is non-secure.
Claims20
A method, comprising:
- providing a first integrated circuit having a security feature;
- and
- providing a second integrated circuit having said security feature,
- wherein the first integrated circuit and the second integrated circuit are formed comprising identical circuitry,
- wherein when the security feature of the first integrated circuit is not enabled, the first integrated circuit comprises a non-secure integrated circuit,
- wherein when the security feature of the second integrated circuit is enabled, the second integrated circuit comprises a secure integrated circuit,
- wherein the secure integrated circuit externally provides a first plurality of signals via a first plurality of terminals, and
- wherein the non-secure integrated circuit externally provides the first plurality of signals via a second plurality of terminals different from the first plurality of terminals, and wherein the non-secure integrated circuit is incapable of externally providing the first plurality of signals via the first plurality of terminals.
A method, comprising:
- providing a first integrated circuit having a security feature;
- and
- providing a second integrated circuit having said security feature,
- wherein the first integrated circuit and the second integrated circuit are formed comprising identical circuitry,
- wherein when the security feature of the first integrated circuit is not enabled, the first integrated circuit comprises a non-secure integrated circuit,
- wherein when the security feature of the second integrated circuit is enabled, the second integrated circuit comprises a secure integrated circuit,
- wherein the secure integrated circuit maps one of a chip select signal or a module to a first address value, and
- wherein the non-secure integrated circuit maps one of said chip select signal or said module to a second address value that is different than the first address value, wherein the non-secure integrated circuit is incapable of mapping said chip select signal to the first address value, and wherein the non-secure integrated circuit is incapable of mapping said module to the first address value.
An integrated circuit, comprising:
- a one time programmable circuit for providing at least one signal for selecting a secure mode;
- multiplexer circuitry coupled to the one time programmable circuit for receiving the at least one signal for selecting the secure mode, the multiplexer circuitry selecting one of a first plurality of signals and a second plurality of signals to provide external to the integrated circuit via a first plurality of terminals;
- decode circuitry coupled to the one time programmable circuit for receiving the at least one signal for selecting the secure mode, the decode circuitry receiving an address value, the decode circuitry decoding said address value in a first manner to select a first decoder output, the decode circuitry decoding said address value in a second manner to select a second decoder output.
Dependencies are inferred from the claim text.