An integrated circuit (IC) test engine can generate a plurality of single cycle test patterns that target a plurality of static single cycle defects of a fabricated IC chip based on an IC design. The IC test engine can also fault simulate the plurality of single cycle test patterns against a plurality of multicycle defects in the IC design, wherein a given single cycle test pattern of the plurality of single cycle test patterns is sim-shifted to enable detection of a given multicycle fault and/or defect of the plurality of multicycle faults and/or defects.

An exemplary method of detecting a Trojan circuit in an integrated circuit is related to applying a test pattern comprising an initial test pattern followed by a corresponding succeeding test pattern to a golden design of the integrated circuit, wherein a change in the test pattern increases side-channel sensitivity; measuring a side-channel parameter in the golden design of the integrated circuit after application of the test pattern; applying the test pattern to a design of the integrated circuit under test; measuring the side-channel parameter in the design of the integrated circuit under test after application of the test pattern; and determining a Trojan circuit to be present in the integrated circuit under test when the measured side-channel parameters vary by a threshold.

A system for testing a circuit comprises scan chains, a controller configured to generate a bit-inverting signal based on child test pattern information, and bit-inverting circuitry coupled to the controller and configured to invert bits of a parent test pattern associated with a plurality of shift clock cycles based on the bit-inverting signal to generate a child test pattern during a shift operation. Here, the plurality of shift clock cycles for bit inverting occur every m shift clock cycles, and the child test pattern information comprises information of m and location of the plurality of shift clock cycles in the shift operation.

Scan channel slicing methods and systems for testing of scan chains in an integrated circuit (IC) reduce the number of test cycles needed to effectively test all the scan chains in the IC, reducing the time and cost of testing. In scan channel slicing, rather than loading and unloading into scan chains high-power patterns having numerous switching transitions over the length of each scan chain, loading and unloading the entirety of the scan chain scan while observing it, chain load data is sliced, apportioning between the different scan chains independently observable sections (slices) of transition data in which all four bit-to-bit transitions (“0” to “0”, “0” to “1”, “1” to 0”, “1” to “1”) are ensured to exist. The remainder of the scan chain load data, which is not observed in the test procedure, can be low-transition data that consumes low dynamic power, such as mostly zeroes or mostly ones.

Electronic scan circuitry includes a decompressor (510), a plurality of scan chains (520.i) fed by the decompressor (510), a scan circuit (502, 504) coupled to the plurality of scan chains (520.i) to scan them in and out, a masking circuit (590) fed by the scan chains (520.i), and a scannable masking qualification circuit (550, 560, 580) coupled to the masking circuit (590), the masking qualification circuit (550, 560, 580) scannable by scan-in of bits by the decompressor (510) along with scan-in of the scan chains (520.i), and the scannable masking qualification circuit (550, 560, 580) operable to hold such scanned-in bits upon scan-out of the scan chains through the masking circuit (590). Other scan circuitry, processes, circuits, devices and systems are also disclosed.

A semiconductor device addresses to a problem in which a current consumption variation rate increases during BIST execution causing resonance noise generation in a power supply line. The semiconductor device includes a self-diagnosis control circuit, a scan target circuit including a combinational circuit and a scan flip-flop, and an electrically rewritable non-volatile memory. A scan chain is configured by coupling a plurality of the scan flip-flops. In accordance with parameters stored in the non-volatile memory, the self-diagnosis control circuit can change a length of at least one of a scan-in period, a scan-out period and a capture period, and can also change a scan start timing.

An integrated circuit (IC) includes first and scan latches that are enabled to load data during a first part of a clock period. A clocking circuit outputs latch clocks with one latch clock driven to an active state during a second part of the clock period dependent on a first address input. A set of storage elements have inputs coupled to the output of the first scan latch and are respectively coupled to a latch clock to load data during a time that their respective latch clock is in an active state. A selector circuit is coupled to outputs of the first set of storage elements and outputs a value from one output based on a second address input. The second scan latch then loads data from the selector's output during the first part of the input clock period.

A method includes identifying state holding pipeline stages in a pipeline path of a design for test (DFT) of an integrated circuit design, splitting each pattern of a plurality of patterns into a first part and a second part, reformatting the plurality of patterns to generate another plurality of patterns such that the first part and the second part of each pattern of the plurality patterns are included in different patterns of the another plurality of patterns. The length of the first part is a function of a number of the identified pipeline stages.

A circuit comprises: a bit-flipping signal generation device comprising a storage device and configured to generate a bit-flipping signal based on bit-flipping location information, the storage device configured to store the bit-flipping location information for a first number of bits, the bit-flipping location information obtained through a fault simulation process; a pseudo random test pattern generator configured to generate test patterns based on the bit-flipping signal, the pseudo random test pattern generator comprising a register configured to be a linear finite state machine, the register comprising storage elements and bit-flipping devices, each of the bit-flipping devices coupled to one of the storage elements; and scan chains configured to receive the test patterns, wherein the bit-flipping signal causes one of the bit-flipping devices to invert a bit of the register each time a second number of test patterns is being generated by the pseudo random test pattern generator during a test.

Described herein are integrated circuit chips having test circuitry designed such that independently selectable testing of different power domains using a same scan chain compressor-decompressor circuit may be performed. Also disclosed herein are integrated circuit chips having test circuitry designed such that independently selectable testing of different power domains using multiple different scan chain compressor-decompressor circuits may be performed.