Abstract: Methods and apparatuses for circuit design to reduce power usage, such as reducing temperature dependent power usage, and/or to improve timing, such as reducing temperature dependent delay or transition time. At least one embodiment of the present invention reduces the power dissipation and improves the timing of an integrated circuit to optimize the design. A thermal analysis is used to determine the temperature dependent power dissipation of a circuit and the temperature distribution of the circuit resulting from dissipating the heat created by the temperature dependent power dissipation. Then, the components of the design are selectively transformed to reduce the power dissipation and to improve timing based on the temperature solution. The transformation may include placement changes and netlist changes, such as the change of transistor threshold voltages for cells or for blocks of the circuit chip.

Abstract: Methods and apparatuses for circuit design are described. In one embodiment, the method comprises determining a distribution of nets of a circuit, the distribution of the nets comprising numbers of blocks that each of the nets has in each of a plurality of partitions of the circuit in a partitioning solution, moving a first block of the circuit from a source partition to a destination partition to modify the partitioning solution, and updating the distribution of the nets after the moving.

Abstract: Methods and apparatuses for approximate functional matching are described including identifying functionally similar subsets of an integrated circuit design or software program, distinguishing control inputs of the subsets from data inputs, and assigning combinations of logic values to the input control signals to capture co-factors for functional matching.

Abstract: Methods and apparatuses to design and analyze digital circuits with time division multiplexing. At least one embodiment of the present invention efficiently models subsystems connected by a TDM channel by introducing equivalent delays in the connections for the subsystems, where the delays are determined according to the upper bounds of the delays caused by the TDM channel. The TDM channel is modeled with its equivalent delays. Thus, a transformation tool is allowed to take into account the original constraints and time budgeting of the sending subsystem and the receiving subsystem. The problem of asynchronous clock domains is eliminated; and, simulation time of the multiplexed circuit is also improved. In some embodiments of the present invention, multiple TDM slots are assigned to a particular signal to reduce the equivalent connection delay caused by the TDM channel for the particular signal.

Abstract: An integrated circuit (IC) comprising a shielding mesh in at least one layer of the IC, the shielding mesh having a first plurality of lines which are designed to provide a first reference voltage and having a second plurality of lines which are designed to provide a second reference voltage and wherein the shielding mesh comprises a window in which signal lines are routed with less shielding than signal lines which are routed in the shielding mesh. The IC further comprising power supply lines in at least a first layer of the IC, the first layer being different than the at least one layer which contains the shielding mesh, the power supply lines being coupled to the shielding mesh and being larger in width than the first plurality of lines and the second plurality of lines.

Abstract: Methods and apparatuses for designing at least one integrated circuit (IC). In one embodiment, the method comprises partitioning a circuit into portions that represent a partitioning solution and assigning traces to interconnect the portions to generate a trace assignment solution. The method further comprises optimizing the circuit through a modification of at least one of the partitioning solution and the trace assignment solution, the optimizing based on evaluating a design parameter which is based at least in part on the trace assignment solution.

Abstract: Methods and apparatuses for approximate functional matching are described including identifying functionally similar subsets of an integrated circuit design or software program, distinguishing control inputs of the subsets from data inputs, and assigning combinations of logic values to the input control signals to capture co-factors for functional matching.

Abstract: Methods and apparatuses to time-share resources having internal states are described. A first design of a system having a plurality of instances of a logical block to perform logical operations is received. The instances may have internal states. The system is automatically transformed to generate a second design having a fewer quantity of time-shared instances of the logical block. The plurality of the instances in the first design is replaced with the fewer time-shared instances in the second design. The time-shared instances in the second design have elements to time multiplex the internal states.

Abstract: In one aspect of an embodiment, a method implemented on a data processing system for circuit design, includes identifying one or more first portions of a design of a circuit, each of the one or more first portions containing a set of elements interconnected via timing nets and generating weights for the timing critical nets, the weights being generated after identifying the one or more first portions and executing a placer algorithm which uses the weights for the timing critical nets to place the set of elements on a representation of the design. In this method, in one embodiment, the weights for the timing critical nets can be generated to have values that differ from weights for non-critical nets. The placer algorithm can be any one of a variety of conventional placer algorithms such as a weighted wire length driven placer algorithm or a force directed timing driven placer algorithm or a min-cut placer algorithm.

Abstract: A method and system for debugging using replicated logic and trigger logic is described. A representation of a circuit is compiled. One or more signals are selected for triggering and trigger logic is inserted into the circuit. A portion of the circuit is selected for replication. The selected portion of the circuit is replicated and delay logic is inserted to delay the inputs into the replicated portion of the circuit. The representation of the circuit is recompiled and programmed into a hardware device. A debugger may then be invoked. One or more of the triggering signals are selected. For each selected triggering signal, one or more states are selected to setup a trigger condition. The hardware device may then be run. The replicated portion of the circuit will be paused when the trigger condition occurs. The states of registers in the replicated portion of the circuit and the sequence of steps that led to the trigger condition may then be recorded.

Abstract: Methods and apparatuses to design an Integrated Circuit (IC) with a shielding of wires. In at least one embodiment, a shielding mesh of at least two reference voltages (e.g., power and ground) is used to reduce both the capacitive coupling and the inductive coupling in routed signal wires in IC chips. In some embodiments, a type of shielding mesh (e.g., a shielding mesh with a window surrounded by a power ring, or a window with a parser set of shielding wires) is selected to make more routing area available in locally congested areas. In other embodiments, the shielding mesh is used to create or add bypass capacitance. Other embodiments are also disclosed.

Abstract: Methods and apparatuses for an Integrated Circuit (IC) with a shielding of wires. In at least one embodiment, an integrated Circuit (IC) device comprises a first plurality of signal wires disposed within a substrate a shielding mesh disposed on the substrate. In at least one embodiment, the shielding mesh comprises a first plurality of connected wires for a first reference voltage and a second plurality of connected wires for a second reference voltage. Wherein at least a first portion of each of the first plurality of the signal wires is shielded between one of the first plurality of connected wires and one of the second plurality of connected wires from adjacent signal wires and a second portion of the first plurality of signal wires are adjacent to each other in a region defined by the first and second pluralities of connected wires.

Abstract: In one aspect of an embodiment, a method implemented on a data processing system for circuit design, includes: identifying one or more first portions (e.g., islands) of a design of a circuit, where each of the one or more first portions contains a set of elements interconnected via timing critical nets; and reporting inter-dependency between portions of the circuit in view of the one or more first portions. In one aspect of an embodiment, a method implemented on a data processing system for circuit design, includes: identifying a first portion (e.g., island) of a design of a circuit, the first portion containing a set of elements interconnected via timing critical nets; and performing a synthesis transformation of the first portion to isolate timing dependency of the first portion on a non-critical net connected to an element of the first portion.

Abstract: Methods and apparatuses for designing at least one integrated circuit (IC). In one embodiment, the method comprises partitioning a circuit into portions that represent a partitioning solution and assigning traces to interconnect the portions to generate a trace assignment solution. The method further comprises optimizing the circuit through a modification of at least one of the partitioning solution and the trace assignment solution, the optimizing based on evaluating a design parameter which is based at least in part on the trace assignment solution.

Abstract: Methods and apparatuses to automatically synthesize circuits. In one aspect of an embodiment, a logic function feeding a carry chain is implemented through extending the carry chain and through using the extended portion of the carry chain. In one aspect of an embodiment, control/non-control loads are separated from each other through replicating the driver elements of the mixed control/non-control loads. In one aspect of an embodiment, a read only memory (ROM) is implemented using a random access memory (RAM). In one embodiment, a register at the input side of the ROM is generated through inserting a register that is clocked at an inverted clock signal or through retiming a register from the output side of the ROM.

Abstract: Methods and apparatuses to design an Integrated Circuit (IC) with a shielding of wires. In at least one embodiment of the present invention, a shielding mesh of at least two reference voltages (e.g., power and ground) is used to reduce both the capacitive coupling and the inductive coupling in routed signal wires in IC chips. In some embodiments, a type of shielding mesh (e.g., a shielding mesh with a window surrounded by a power ring, or a window with a parser set of shielding wires) is selected to make more routing area available in locally congested areas. In other embodiments, the shielding mesh is used to create or add bypass capacitance. Other embodiments are also disclosed.

Abstract: Methods and apparatuses to automatically modify a circuit design (e.g., a synthesis solution) according to the sensitivity in design parameters with respect to the possible deviation in the subsequent implementation (e.g., placement and routing) of the circuit. In one aspect of the present invention, a method to design a circuit includes: determining likelihood of a design constraint being violated in an implementation of a first circuit design (e.g., a technology specific netlist with or without a placement solution); and, modifying the first circuit design to reduce the likelihood of the design constraint being violated. In one example, the implementation of the first circuit design includes a routing solution for implementing the first circuit design; and, the first circuit is modified through sizing an instance of a logic element, buffering a signal, load shielding for a signal, or other operations.

Abstract: Methods and apparatuses to optimize integrated circuits by identifying functional modules in the circuit having similar functionality that can share circuit resources and producing a modified description of the circuit where the similar functional modules are folded onto common circuit resources and time-multiplexed using an original system clock or a fast clock.

Abstract: Methods and apparatuses for incremental circuit partitioning and incremental trace assignment. In one embodiment of the present invention, a cost function based on both the partitioning solution and the trace assignment solution is used for the partitioning of a circuit; in reducing the cost function, blocks of circuits are moved among partitions and the trace assignment are updated accordingly to evaluate the cost function. In one embodiment, the traces and nets are grouped according to the partitions they connect for trace assignment. In one embodiment, a flow diagram is constructed for assigning nets to traces; and, maximum flow algorithms are used. In one embodiment, a flow diagram includes feedthrough solutions, in which flow conservation is not preserved at certain nodes. In one embodiment, integer linear programming techniques are used for assigning nets to traces.

Abstract: Methods and apparatuses to design an Integrated Circuit (IC) with a shielding of wires. In at least one embodiment, a shielding mesh of at least two reference voltages (e.g., power and ground) is used to reduce both the capacitive coupling and the inductive coupling in routed signal wires in IC chips. In some embodiments, a type of shielding mesh (e.g., a shielding mesh with a window surrounded by a power ring, or a window with a parser set of shielding wires) is selected to make more routing area available in locally congested areas. In other embodiments, the shielding mesh is used to create or add bypass capacitance. Other embodiments are also disclosed.