Nxp B.v.

Martin Heinrich Butkus

Ventzislav Nikov

Andreas Lentz

Stefan Heyse

Oliver Alexander Schmidt

A protection circuit for a Sbox, including: a first check circuit configured to determine if a most significant bit (MSB) part input into a first multiplier of the Sbox is zero; a second check circuit configured to determine if a CCn value input into the first multiplier and a second multiplier of the Sbox is zero; a third check circuit configured to determine if a least significant bit (LSB) part input into a first multiplier of the Sbox is zero; and a first Statistical Ineffective Fault Analysis (SIFA) logic circuit configured to produce a first output to indicate a SIFA attack when one of the following conditions is satisfied: both the MSB part and the LSB part are zero and the CCn value is not zero: or the CCn value is zero and either of the MSB part and LSB part are not zero.

Statistical ineffective fault analysis protection of Sbox

A fully digital method and apparatus are provided for detecting glitches on a monitored line by providing a toggle signal to an initial delay circuit and a plurality of delay elements formed with standard logic cells so that logic values from the delay elements are captured in a corresponding plurality of clocked capture flops to provide a digitized representation of a delay value during a sampling period which is converted to a numerical measurement result which is evaluated against a reference value to generate an output error signal if a difference between the numerical measurement result and reference value exceeds a programmable margin, where the initial delay circuit is configured with a trim setting to impose an initial delay to compensate for process variations and where the reference value is adapted over a plurality of sampling periods to compensate for temperature effects on the numerical measurement result.

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Hamburg, Germany

Martin Heinrich Butkus