Disclosed herein is a single integrated circuit chip including main logic that operates a vehicle component such as a valve driver. Isolated from the main logic within the chip is a safety area that operates to verify proper operation of the main logic. A checker circuit within the chip outside of the safety area serves to verify proper operation of the checker circuit. The checker circuit receives signals from the safety circuit and uses combinatorial logic circuit to verify from those signals that the check circuit is operating properly.

The disclosure describes a process and apparatus for accessing devices on a substrate. The substrate may include only full pin JTAG devices (504), only reduced pin JTAG devices (506), or a mixture of both full pin and reduced pin JTAG devices. The access is accomplished using a single interface (502) between the substrate (408) and a JTAG controller (404). The access interface may be a wired interface or a wireless interface and may be used for JTAG based device testing, debugging, programming, or other type of JTAG based operation.

Systems, methods, and apparatuses are described for verifying the authenticity of an integrated circuit device. An integrated test apparatus may use quiescent current and/or conducted electromagnetic interference readings to determine if a device under test matches the characteristics of an authenticated device. Deviations from the characteristics of the authenticated device may be indicative of a counterfeit device.

In one embodiment, a device comprises: a first die having disposed thereon a first plurality of latches wherein ones of the first plurality of latches are operatively connected to an adjacent one of the first plurality of latches; and a second die having disposed thereon a second plurality of latches wherein ones of the second plurality of latches are operatively connected to an adjacent one of the second plurality of latches. Each latch of the first plurality of latches on said first die corresponds to a latch in the second plurality of latches on said second die. Each set of corresponding latches are operatively connected. A scan path comprises a closed loop comprising each of said first and second plurality of latches. One of the second plurality of latches is operatively connected to another one of the second plurality of latches via an inverter.

A detection result recording and outputting device of an IC is operable to record and output detection results at different speeds respectively. The device includes a sensing circuit, a decision circuit, a storage circuit, and a control circuit. The sensing circuit detects the variation in a characteristic of a target circuit and generates detection results at a first speed. The decision circuit receives the detection results and generates a trigger signal or changes its level when finding that a detection result satisfies a predetermined condition. The control circuit writes the detection result and subsequent (N−1) detection results into the storage circuit at a second speed according to the trigger signal, and then reads out the detection results from the storage circuit at a third speed and outputs them at a fourth speed. The second speed is not higher than the first speed, but higher than the fourth speed.

A device comprises a first die; and a second die stacked below the first die with interconnections between the first die and the second die. A least one of the first die or the second die has a circuit for performing a function and provides a functional path. Each of the first and second dies comprise a plurality of latches, including a respective latch corresponding to each one of the interconnections; and a plurality of multiplexers. Each multiplexer is connected to a respective one of the plurality of latches and arranged for receiving and selecting one of a scan test pattern or a signal from the functional path for outputting during a scan chain test of the first die and second die.

A test mode signal is generated to include a test pattern and an error reporting sequence. The test mode signal is sent on link that includes one or more extension devices and two or more sublinks. The test mode signal is to be sent on a particular one of the sublinks and is to be used by a receiving device to identify errors on the particular sublink. The error reporting sequence is to be encoded with error information to describe error status of sublinks in the plurality of sublinks.

A chip and a chip test method are provided. The chip includes a receiver circuit and a test circuit. The receiver circuit includes a signal receiving unit and a signal bump. The signal bump is coupled to the signal receiving unit. The test circuit is coupled to a circuit node between the signal receiving unit and the signal bump. The test circuit includes a digital-to-analog converter, a first resistor, and a unit gain buffer. A first terminal of the first resistor is coupled to the circuit node. An output terminal of the unit gain buffer is coupled to a second terminal of the first resistor. A first input terminal of the unit gain buffer is coupled to an output terminal of the digital-to-analog converter. A second input terminal of the unit gain buffer is coupled to an output terminal of the unit gain buffer.

Methods and systems for authenticating electronic devices via multi tone analysis. A method for authenticating a device under test (DUT) of a type of DUT includes imparting voltage tones to the DUT. The voltage tones are proximate a frequency of interest that is associated with the type of DUT. Using a measurement response of the DUT to the voltage tones, an electronic signature of the DUT is determined. The DUT is determined to be authentic when the electronic signature of the DUT substantially matches an electronic signature of an authority DUT of the type of DUT.

Fault detection circuitry and a corresponding method are disclosed. A count value that is indicative of the switching period of a PWM signal is determined and it is determined whether this count value is between a first threshold and a second threshold. An error signal is generated when the switching period is not between the first and the second threshold. A count value that is indicative of the switch-on duration of the PWM signal is determined and compared with a switch-on threshold in order to determine whether the switch-on duration is greater than a maximum switch-on duration. A count value that is indicative of the switch-off duration of the PWM signal is determined and compared with a switch-off threshold in order to determine whether the switch-off duration is greater than a maximum switch-off duration. Error signals can be generated when the durations are greater than the maximum durations.