摘要:
A method and a circuit for checking the coherence between data read from a first area of a memory of a microcontroller and the address of these data, including calculating a current digital signature of the read data by a function also taking into account the address of these data in the memory, and checking the coherence between the current signature and a previously-recorded signature.
摘要:
A method and a circuit for protecting a digital quantity over a first number of bits, in an algorithm executing at least one modular exponentiation of data by the quantity, the steps including at least one squaring up and at least one multiplication and implementing, for each bit of the quantity, different calculation steps according to the state of the bit, a same number of multiplications being performed whatever the state of the bit and all the calculation steps using a multiplication being taken into account to calculate a final result.
摘要:
A device includes a serial port for connecting as a slave to a master device through a serial link. The device further includes a detection circuit for detecting the presence of an impedance of the master device, linked to a terminal of the serial port. The device can be used with microprocessor cards comprising a USB port.
摘要:
A method and a circuit for protecting an integrated circuit against an extraction of data read from at least one memory, comprising the steps of comparing each data word to be output from the integrated circuit with at least one value stored in this circuit, and generating an error signal in case of an identity between the value and the data waiting to be output.
摘要:
A data communication device comprises an input circuit (DRTC) that converts external data (XDT) into internal data (IDT) on the basis of a sampling signal (SP). A synchronization circuit (SYNC) provides the sampling signal (SP) on the basis of an oscillator signal (OS) and a synchronization value (SV). The synchronization value (SV) is representative of a number of cycles of the oscillator signal (OS) contained within a time interval for a unit of external data. The synchronization value (SV) is an initial value (IV) during an initial synchronization phase and a measured value (MV) during a measurement-based synchronization phase. A control circuit (IFC) carries out a calibration step in which the initial value (IV) is a preprogrammed reset value (RV) and in which the measured value (MV) is stored as a calibration value (CV). The control circuit (IFC) applies the calibration value (CV) as the initial value (IV) in subsequent initial synchronization phases.
摘要:
An electronic circuit (CE) is provided with an oscillator (OSC—1) outputting a signal (S1) with a frequency (F1) varying as a function of the temperature (Tc) of this circuit, and receiving or outputting a signal (S2) with a fixed and known frequency (F2). This circuit includes a measurement module (MSR) outputting a measurement signal (Φ1) representative of the variable frequency (F1) evaluated using the fixed frequency signal (S2) used as a reference or standard, and a conversion module (CVRS) applying a transfer function (u−1, v−1, or w−1) that is the inverse of the function for the variation of the frequency of the first signal (S1) as a function of the temperature, to the measurement signal (Φ1), in order to output a signal (Φc) representative of the circuit temperature (Tc).
摘要:
A method and a circuit for protecting a digital quantity over a first number of bits, in an algorithm executing at least one modular exponentiation of data by the quantity, the steps including at least one squaring up and at least one multiplication and implementing, for each bit of the quantity, different calculation steps according to the state of the bit, a same number of multiplications being performed whatever the state of the bit and all the calculation steps using a multiplication being taken into account to calculate a final result.
摘要:
A secure device includes a memory capable of storing information. The secure device also includes a secure microcontroller capable of securing the information in the memory. The secure microcontroller includes a plurality of registers. The secure microcontroller also includes combinatorial logic capable of receiving at least one output value provided by at least one of the registers. The combinatorial logic is also capable of performing one or more combinatorial operations using the at least one received output value. In addition, the secure microcontroller includes dummy cycle circuitry capable of causing one or more of the registers and the combinatorial logic to change state and consume current during one or more dummy cycles.
摘要:
A method and a circuit for protecting an integrated circuit against an extraction of data read from at least one memory, comprising the steps of comparing each data word to be output from the integrated circuit with at least one value stored in this circuit, and generating an error signal in case of an identity between the value and the data waiting to be output.
摘要:
An electronic circuit (CE) is provided with an oscillator (OSC—1) outputting a signal (S1) with a frequency (F1) varying as a function of the temperature (Tc) of this circuit, and receiving or outputting a signal (S2) with a fixed and known frequency (F2). This circuit includes a measurement module (MSR) outputting a measurement signal (Φ1) representative of the variable frequency (F1) evaluated using the fixed frequency signal (S2) used as a reference or standard, and a conversion module (CVRS) applying a transfer function (u−1, v−1, or w−1) that is the inverse of the function for the variation of the frequency of the first signal (S1) as a function of the temperature, to the measurement signal (Φ1), in order to output a signal (Φc) representative of the circuit temperature (Tc).