Freescale Semiconductor,inc.

Nxp Usa, Inc.

Prashant Bhargava

Mohit Arora

Rohit Tomar

Kumar Abhishek

Rakesh Pandey

Martin Mienkina

Matthew B Ruff

Neha Jain

James Robert Feddeler

Michael A Stockinger

Charles Eric Seaberg

Dale John McQuirk

Simon Gallimore

Rishi Bhooshan

Siddi Jai Prakash

Sarthak Mittal

Kshitij Bajaj

Pushkar Sareen

Sudhi R Proch

An active tamper detection circuit with bypass detection is provided. A bypass detection circuit is coupled to an active mesh loop. The bypass detector includes a voltage comparator with a variable hysteresis control circuit and a calibration engine. The bypass detector detects a change in impedance in the mesh when an attacker attempts to bypass the active loop using a wire. As part of a boot-up sequence, the calibration engine runs a hysteresis sweep on the voltage comparator and stores a hysteresis sweep boot-up signature. When bypass protection is enabled, the bypass detector runs a hysteresis sweep of the voltage comparator periodically at a predetermined interval. Each sweep generates a generated signature that is compared to the stored boot-up signature. Any signature mismatch will be signaled as an impedance mismatch, or tamper. The hysteresis step size is also programmable. The calibration engine can make small changes to the boot-up signature to allow for small voltage variations.

Active tamper detection circuit with bypass detection and method therefor

A processing system includes a processor and a temperature security module coupled to provide a temperature tamper signal to the processor. The temperature security module includes a shelf mode trim value, an operating mode trim value, and a programmable temperature trim value. One of the programmable temperature trim value, the shelf mode trim value, and the operating mode trim value, is used based on a deployment mode of the processing system to set a temperature monitor trim value.

Data processing system with temperature monitoring for security

A tamper detector has tamper detection logic connected to tamper detection ports through a tamper detection interface. A real-time clock (RTC) provides a clock signal and has a battery. A processor is powered by an external power supply in a powered operational mode and has a power-off mode. In a wake-up configuration, a wake-up signal on a specific I/O port awakens the external power supply from the power-off mode to supply power to the RTC and the tamper detection interface when power from the battery is unavailable. The tamper detection ports continue to function despite removal or discharge of the battery without ESD concerns. The specific I/O port optionally may be configured for passive tamper detection.

Tamper detector power supply with wake-up

A microcontroller includes a clock generator having an internal reference clock, a system mode controller establishing an operating mode, a flash memory having an internal clock and a non-volatile option register, and a boot mode selection logic circuit coupled to the system mode controller and the flash memory. The logic circuit outputs a boot mode selection signal instructing the microcontroller to boot in a very low power run (VLPR) mode or a RUN mode. The system mode controller enters the VLPR or RUN mode in response. The flash memory bypasses and disables its internal clock prior to calibration of the flash memory in the VLPR mode and prior to initialization of the flash memory in the RUN mode. The flash memory subsequently uses an external clock signal based on the output of the internal reference clock.

Method for low power boot for microcontroller

A system for performing diagnostic checks on a data message transmitted from a sensor and received by a receiver includes a receiver clock tick counter, a prescaler counter, a calibration pulse detector, a nibble counter, and a calculator. The system receives first and second data messages transmitted from the sensor. Pulse widths of first and second calibration pulses of the first and second data messages, respectively, and lengths of the first and second data messages are measured using the receiver clock tick, prescaler, and nibble counters based on a compensated receiver clock signal. Thereafter, the pulse widths of the first and second calibration pulses and the lengths of the first and second data messages are compared using the calculator to perform the diagnostic checks.

Channel diagnostic system for sent receiver

A system for generating a tamper detection signal indicating tampering with one or more circuits of an integrated circuit (IC) includes a tamper detection module, and wire-pairs connected to the tamper detection module and arranged in a winding configuration to form a wire-mesh. The wire-mesh is placed a predefined distance from the circuits. The tamper detection module generates and provides serial bit-streams to the wire-pairs for detecting a breach in the wire-mesh by an external probe.

System for preventing tampering with integrated circuit

A memory error management system connected to memory channels for managing errors detected in corresponding memory devices includes a reporting table including a list of historically reported errors, a binary value representing the current error status of the memory channels, a uniqueness check module for checking whether a historically reported error is reappearing as a current error, an error mask register for generating a masked binary value representing unique current errors in the memory channels, and a channel arbitration module for decoding the channel identifiers of corrupted memory channels from the masked binary value and storing the decoded channel identifiers into the reporting table.

Memory error management system

A tamper detector has input and output pins for connection to ends of a tamper detection circuit, and a corresponding set of linear feedback shift registers (LFSRs) timed by clock signals for generating pseudo-random coded detection signals as a function of seed values and of a generator polynomial defined by feedback taps. A comparator compares signals received from the detection circuit with the coded detection signals. A multiplexer provides the coded detection signal selectively from the LFSRs to the output pin and the comparator. A controller varies the seed values for different cycles of values of the pseudo-random coded detection signals. The controller also controls the generator polynomial and a frequency of the clock signals for different cycles of values of the pseudo-random coded detection signals.

Tamper detector for secure module

A system for compensating for variations in the frequency of an input clock signal having a first frequency includes a coarse counter that receives the input clock signal, counts a predetermined number of clock pulses of the input clock signal, and generates a coarse compensated clock signal having a second frequency. A first compensation module adjusts a clock pulse of the input clock signal based on a coarse compensation value. A residual period adjustment module accumulates a fine compensation value for each clock pulse of the coarse compensated clock signal. A fine counter operates at a third frequency of a fine clock signal, receives an adjusted delay value based on the accumulated fine compensation value, counts a number of fine clock pulses in each clock pulse of the coarse compensated clock signal, and generates a fine compensated clock signal having the second frequency.

System for compensating for variations in clock signal frequency

A method and system for estimating and compensating for variation between a receiver clock and a transmitter clock, where a receiver utilizes a high frequency clock signal to generate a receiver clock and then adjusts the receiver clock to compensate for variations between the receiver and transmitter clocks. The adjusted receiver clock is used to sample nibble pulses in a received data frame. Counter based compensation of the receiver clock eliminates the need for the receiver to perform floating point calculations, improves the accuracy of nibble pulse sampling and also reduces area and power consumption of the device.

Estimation and compensation of clock variation in received signal

A circuit and method for synchronizing signals between asynchronous clock domains within digital electronic circuits decouples asynchronous clocks. The timing of the slower clock is used to prevent read and write to counters so that write signals from the fast clock domain can be directly used in the slower clock domain when the counters are not toggling. This feature removes the need for sampling and holding the data on the fast clock, which would require consume additional power and require additional circuit area.

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Gurgaon, India

Prashant Bhargava