A circuit includes a dynamic core data register (DCDR) cell that includes a data register, a shift register and an output circuit to route the output state of the data register or the shift register to an output of the DCDR in response to an output control input. A clock gate having a gate control input controls clocking of the shift register in response to a first scan enable signal. An output control gate controls the output control input of the output circuit and controls which outputs from the data register or the shift register are transferred to the output of the output circuit in response to a second scan enable signal. The first scan enable signal and the second scan enable signal to enable a state transition of the shift register at the output of the DCDR.

Sensor data relating to operating conditions for an integrated circuit are read out through scan chains. Scan tests are run on an integrated circuit containing logic circuits that implement logic functions. The logic circuits are interconnected to form scan chains which are used in running the scan tests. The scan test data resulting from the scan tests is read out from the logic circuits through these scan chains. During the scan tests, sensor blocks capture measurements of the operating conditions for the logic circuits. The operating conditions may include process, voltage and/or temperature conditions, for example. The sensor blocks are also interconnected to form one or more scan chains, and sensor data produced from the captured measurements is read out through these scan chains concurrently with the read out of the scan test data.

An unbalanced multiplexer and a scan flip-flop including the unbalanced multiplexer, wherein the unbalanced multiplexer includes a first transmission circuit transmitting a first input signal to an output terminal according to a logic state of a selection signal; and a second transmission circuit transmitting a second input signal to the output terminal according to the logic state of the selection signal. A delay characteristic of a first transmission path from a first input terminal to the output terminal along which the first input signal of the first transmission circuit is transmitted, and a delay characteristic of a second transmission path from a second input terminal to the output terminal along which the second input signal of the second transmission circuit is transmitted, are set differently.

A method for circuit design includes providing one or more wrapper cells for use with a library of standard cells in design of an IC. Each wrapper cell has geometrical dimensions matching a corresponding group of one or more of the standard cells and defines an electrical path, including at least one via, from a location of a terminal in a lower metal layer in the standard cells in the corresponding group to a location in an upper metal layer. A computerized place-and-route tool receives a layout of the IC including a wrapper cell superimposed over one of the standard cells in the corresponding group. The place-and-route tool automatically routes a signal connection through the upper metal layer and the at least one via defined by the superimposed wrapper cell to the predefined signal terminal in the lower metal layer in the one of the standard cells.

A semiconductor device includes a processing block which comprises one or more intellectual property (IP) blocks; a scan chain which is electrically connected to the IP blocks, wherein the scan chain block has a scan in (SI) terminal and a scan out (SO) terminal; a pattern generating circuit which generates a data pattern having a plurality of bits and inputs the data pattern to the scan in (SI) terminal of the scan chain; and an analyzing circuit which determines the degree of degradation of each of the IP blocks based on a result pattern output from the scan out (SO) terminal of the scan chain.

A method for circuit design includes providing one or more wrapper cells for use with a library of standard cells in design of an IC. Each wrapper cell has geometrical dimensions matching a corresponding group of one or more of the standard cells and defines an electrical path, including at least one via, from a location of a terminal in a lower metal layer in the standard cells in the corresponding group to a location in an upper metal layer. A computerized place-and-route tool receives a layout of the IC including a wrapper cell superimposed over one of the standard cells in the corresponding group. The place-and-route tool automatically routes a signal connection through the upper metal layer and the at least one via defined by the superimposed wrapper cell to the predefined signal terminal in the lower metal layer in the one of the standard cells.

A circuit includes a dynamic core data register (DCDR) cell that includes a data register, a shift register and an output circuit to route the output state of the data register or the shift register to an output of the DCDR in response to an output control input. A clock gate having a gate control input controls clocking of the shift register in response to a first scan enable signal. An output control gate controls the output control input of the output circuit and controls which outputs from the data register or the shift register are transferred to the output of the output circuit in response to a second scan enable signal. The first scan enable signal and the second scan enable signal to enable a state transition of the shift register at the output of the DCDR.

An example method for determining test conditions for at-speed transition delay fault tests on semiconductor devices is provided and includes analyzing scan patterns for testing a circuit of a device-under-test (DUT), identifying paths in the circuit activated by the scan patterns, determining behavior of the paths at different test corners, generating a histogram for each scan pattern representing a distribution of paths exhibiting worst-case behavior at corresponding test corners, generating an ordered set of scan pattern-test corner combinations based on the histogram, selecting a threshold for the ordered scan pattern-test corner combinations based on quality metrics, generating an ordered test set including the ordered scan pattern-test corner combinations with the selected threshold, and feeding the ordered test set to a test instrument, the test instrument testing the DUT according to the ordered test set, the tests being performed at the test corners listed above the selected threshold.

A semiconductor device has a cell region including active regions that extend in a first direction and in which are formed components of transistors. The transistors of the cell region are arranged to function as a scan insertion D flip flop (SDFQ). The SDFQ includes a multiplexer serially connected at an internal node to a D flip-flop (FF). The transistors of the multiplexer include data transistors for selecting a data input signal, the data transistors having a first channel configuration with a first channel size, and scan transistors of the multiplexer for selecting a scan input signal, the scan transistors having a second channel configuration with a second channel size. The second channel size is smaller than the first channel size.

A scan chain circuit is provided. The scan chain circuit includes first and second scan flip-flops and a clock generator. Each of the first and second scan flip-flops has a data-in terminal, a scan-in terminal, a clock terminal, and a data-out terminal. The clock terminals of the first and second scan flip-flop receive first and second clock signals respectively. The data-in terminal of the second scan flip-flop is coupled to the data-out terminal of the first scan flip-flop. During a scan shift cycle of the test mode, an enable pulse of a second clock-enable signal is delayed from an enable pulse of a first clock-enable signal, and the clock generator generates the first clock signal according to the scan clock signal and the first clock-enable signal and further generates the second clock signal according to the scan clock signal and the second clock-enable signal.