Abstract: A method for designing a system includes caching a representation of a first subnet with a synthesis result of the first subnet. The synthesis result of the first subnet is utilized for a second subnet in response to determining that a representation of the second subnet is identical to the representation of the first subnet.

Abstract: A memory timing model is provided, which includes an address input, a multiple-bit data input, a multiple-bit data output, a capacity C and a width N. N one-bit wide memory modules are instantiated in parallel with one another between respective bits of the data input and the data output. Each memory module has a capacity of C bits addressed by the address input.

Abstract: A method of calculating electrical interactions of circuit elements in an integrated circuit layout without flattening the entire database that describes the layout. In one embodiment, a hierarchical database is analyzed and resistance and capacitance calculations made for a repeating pattern of elements are re-used at each instance of the repeated pattern and adjusted for local conditions. In another embodiment, a circuit layout is converted into a number of tiles, wherein the resistance and capacitance calculations made for the circuit elements in the center and a boundary region of the tiles are computed separately and combined. Environmental information that affects electrical interaction between circuit elements in different levels of hierarchy is calculated at a lower level of hierarchy so that such calculations do not need to be made for each placement of a repeated cell and so that not all interacting elements need to be promoted to the same hierarchy level to compute the electrical interactions.

Abstract: Method and apparatus are described for generating a block diagram of an electronic circuit design. In one embodiment, each instance of a multi-master bus, a bus master of a multi-master bus, a bus slave of a multi-master bus, a memory, a co-processor and an input/output port is are identified. Instances of input/output ports are placed about a perimeter of a first area of the diagram. Each instance of a multi-master bus is placed in a bus area within the first area and each bus master is placed in a master area. The bus slaves of a bus are collected in a group, and the group is placed as a single block in a slave area within the first area. The group of bus slave slaves is aligned with a bus master. A diagrammatic representation is output consistent with the placement representations.

Abstract: In a standard cell synthesizing step 101, a net list is synthesized from an RTL description, and an instance name list is formed which contrasts a register description portion with an instance name contained in the net list; in a simulation step 103, an operation simulation written by the RTL description is carried out; the toggle information among registers which is extracted in the simulation step 103 is recorded in a toggle storing step 104, a flip-flop-to-flip-flop toggle information database is constructed in which the recorded toggle information corresponds to a flip-flop-to-flip-flop instance name obtained from the instance name list in a mapping step 105; and in an electric power optimizing step 102, a physical designing operation for reducing power consumption is optimized by employing the net list, the flip-flop-to-flip-flop toggle information database, and a timing restriction.

Abstract: Method and apparatus for generating a test program for an integrated circuit having an embedded processor. One embodiment has a system which includes an embedded microprocessor; a plurality of assembly language instructions stored in a memory, where the assembly language instructions substantially exercise a critical path or a path closest to the critical path in the embedded microprocessor; and programmable test circuitry having a programmable clock circuit for providing a multiplied clock signal to the embedded microprocessor in order to execute the assembly language instructions.

Abstract: A timing analysis apparatus includes a data extracting unit that extracts objective circuit data concerning an objective circuit to become an objective of a timing analysis from layout data indicating circuits on a large-scale-integration chip; a time calculating unit that calculates a delay time of the objective circuit based on the objective circuit data; a parameter calculating unit that calculates a parameter indicating a size of an arrangement area of the objective circuit based on the objective circuit data; an information calculating unit that calculates variation information concerning a variation of the delay time; and a timing analyzing unit that performs the timing analysis of the objective circuit using the delay time and the variation information.

Abstract: A computer implemented method and system for automatically generating a net list for a printed circuit board are described. Selection of one or more pins on a first and second component to be connected is based on one or more of a logical definition, an electrical definition, a distance property, and a programmable constraint. Once pins of the first and second connections are selected and connected, a net list is automatically generated. The net list includes information associated with the first component, information associated with the second component and at least one pin of the second component.

Abstract: Structures and methods that can be used to reduce power consumption in programmable logic devices (PLDs). Varying delays on the input paths of a PLD lookup table (LUT) can cause the nodes within the LUT (including the LUT output signal) to change state several times each time the input signals change state. Therefore, a programmable logic block for a PLD is provided that registers the LUT input signals instead of, or in addition to, the LUT output signal. The delays on the input paths are equalized and “glitching” on the LUT nodes is greatly reduced or eliminated. Thus, power consumption is reduced. Methods are also provided of reducing power consumption in PLDs by replacing single-bit registers on LUT output signals with multi-bit registers on LUT input signals, or by including multi-bit input registers in addition to the single-bit output registers.

Abstract: Method and apparatus for implementing a pre-implemented circuit design for a programmable logic device is described. In one example, a definition of the pre-implemented circuit design is obtained (504). The definition includes a first physical implementation and a first logical implementation. A second logical implementation is produced (506) for an instance of the pre-implemented circuit design using the first logical implementation. A second physical implementation is produced (510, 512) for then instance of the pre-implemented circuit design using the first physical implementation.

Abstract: Valid implementations of functions with programmable logic blocks are efficiently determined by creating an approximation of a hardware configuration of programmable logic blocks to quickly screen out configurations unlikely to provide a valid results. If a configuration passes this first phase, the approximation is refined to search for valid function implementations with the hardware configuration. The approximation and refinement may use a partitioning of function input variables to logic blocks to reduce the search space. Additional conflict clauses may be used to further reduce the search space. Implementations of sample functions or other previously considered functions may be analyzed to identify conflict clauses that are reusable for analyzing other functions. A representation of potential implementations of a function can be subdivided into subsets and analyzed separately. The intersection of the solutions from each subset are valid implementations of the function.

Abstract: A method of controlling an optimal cost is proposed, which can be applied to a circuitry designing process for making electronic products, allowing a user in drawing a circuitry to choose elements of identical specification with different unit prices, thereby achieving the objective of cost-optimization. The cost-optimization method comprises the steps of: first, integrating data of each of the elements of identical specification at different unit prices to form an element database; then, choosing each of the required elements for drawing the circuitry according to the data stored in the element database. The method provides an element database capable of storing and displaying electronic elements of identical specification with different unit prices for the users' selection, thereby achieving a primary objective of effectively controlling an optimal cost in circuitry designing.

Abstract: In one embodiment, the invention is directed to a method of optimizing post-silicon test coverage for a system under test (“SUT”). The method comprises defining coverage data comprising Hardware Description Language (“HDL”) events; testing the SUT using a system exerciser connected to the SUT; comparing the results of the testing with the coverage data to identify underutilized areas of functionality of the SUT; and responsive to the comparing operation, performing additional tests.

Abstract: In the design of a structured ASIC device that is intended to be functionally equivalent to a programmed FPGA, an initial design for the structured ASIC may be modified in any of several ways to improve various aspects of its performance. For example, for critical or near-critical parts of the structured ASIC design, attempts may be made to permute inputs to improve performance. Alternatively or in addition, Shannon's decomposition or other decomposition may be attempted to move a critical input closer to the output of a cell. Another possible modification is replacement of high-speed adders with slower-speed adders in non-critical parts of the structured ASIC design.

Abstract: A novel approach to cross-talk analysis takes effective account of the nature of cross-talk interference. This approach employs conservative assumptions regarding (1) the equivalent output resistance, and (2) the definition of noise immunity for the victim gate. Also, this approach uses signal and noise current metrics in modeling the parameters of the active device elements. This approach provides an expectation of detection and elimination of noise hazards that might otherwise not be undetected.

Abstract: A lithographic mask is illuminated with light from different directions such that intensities of a plurality of incident beams of light provide a largest possible integrated process window defined in terms of an allowed range for defining shapes. Constrained sets of intensity parameters are imposed. A first set of intensity parameters represents maximum possible intensities that can be permitted for overexposed tolerance positions. A second set of intensity parameters represents minimum possible intensities that can be permitted for underexposed tolerance positions. Optimum source intensities of incident beams are defined using a linear program and constraints. The optimum source intensities maximize an integrated range of dose and focal variations without causing printed shapes to depart from the allowed range. Apparatus are detailed and variations are described.

Abstract: A macrocell including a physical layer circuit includes a transmitter circuit and a receiver circuit connected with pads for differential signals DP and DM. The transmitter circuit includes a transmission driver which drives a signal line for the DP and a transmission driver which drives a signal line for the DM. When a direction from a side SD1 to a side SD3 of the macrocell is defined as a first direction, the transmission drivers are disposed on the side of the pads for the DP and DM in the first direction and are disposed line-symmetrically about a line SYL, and the receiver circuit is disposed on the side of the transmitter circuit in the first direction. A routing region of signal lines SLR1 and SLR2 for connecting the receiver circuit with the pads for the DP and DM is provided in the region between the transmission drivers.

Abstract: A circuit design that contains at least two clock domains is simulated using a novel system and method for injecting the effects of metastability. The system includes detectors for detecting, during simulation, when a clock in a transmit clock domain and a clock in a receive clock domain are aligned and when the input of a register receiving a clock-domain-crossing signal is changing. The system includes coverage monitors for measuring, during simulation, statistics related to metastability injection. The system accurately models the effects of metastability by, at appropriate times during simulation, pseudo-randomly inverting outputs of registers receiving clock-domain-crossing signals. By accurately modeling the effects of metastability, errors in the circuit design can be detected while simulating a pre-existing simulation test. The simulation with metastability effects injection is repeatable and requires no modification of pre-existing RTL design files or simulation test files.

Abstract: Signal distribution of a regional signal is described. A programmable logic device includes a global signal distribution network, a regional signal distribution network and a regional buffer. The regional buffer has an output coupled at an end of the regional signal distribution network. The regional signal distribution network is coupled to a configurable logic block via an interconnect tile. The regional buffer is coupled to a regional clock capable input/output block. Additionally described is a source synchronous interface for regional signal distribution.

Abstract: An element placement check system for checking element placement on a printed wiring board having wiring by which a power supply terminal of an integrated circuit and a power supply decoupling element for the power supply terminal are connected on a mounting surface on which the integrated circuit is mounted, wherein the wiring is connected to a power supply plane for providing a direct current power supply to the power supply terminal through a power supply via hole, including: element distance detecting means detecting a first wire length between the power supply decoupling element and the power supply terminal; power supply via hole distance detecting means detecting a second wire length between the power supply via hole and the power supply terminal; and determination means determining a positional relationship of the power supply decoupling element and the power supply via hole to the power supply terminal based on the first and second wire lengths, thereby providing a check system and a printed wiring b