Abstract: An aspect of the invention relates to modeling a transistor in an integrated circuit design. Layout data for the integrated circuit design is obtained. A geometry relating the transistor to at least one well edge of at least one implant well is extracted from the layout data. An effective well proximity value for the transistor is calculated based on the at least one well edge using a complementary error function. The transistor is modeled using the effective well proximity value. In one embodiment, the effective well proximity value is added to a post-layout extracted netlist for the integrated circuit design. The integrated circuit design may be simulated using the post-layout extracted netlist. The effective well proximity value may be used to calculate a threshold voltage for the transistor during the step of simulating the integrated circuit.

Abstract: An integrated circuit has a transistor with an active gate structure overlying an active diffusion area formed in a semiconductor substrate. A dummy gate structure is formed over a diffusion area and separated from the active gate structure by a selected distance (d2). A stress layer overlying the transistor array produces stress in a channel region of the transistor.

Abstract: Various approaches for improving an integrated circuit layout. In one approach, a tree-type hierarchical layout representation of the circuit design is traversed. At each block visited during the traversing, a process determines whether there exists an improvement opportunity for each cell associated with the block. In response to determining that an improvement opportunity exists for a cell of a first block of the plurality of blocks, the process determines whether a modification to the cell satisfies one or more rules for every other block of the block type of the first block in the hierarchical representation. If the rules are satisfied, the modification is stored. Otherwise, the modification is discarded.

Abstract: An integrated circuit (100) has a transistor with an active gate structure 108 overlying an active diffusion area 112 formed in a semiconductor substrate 126. A dummy gate structure 110 is formed over a diffusion area and separated from the active gate structure by a selected distance (d2). A stress layer (130) overlying the transistor array produces stress in a channel region (107) of the transistor.

Abstract: Computer-implemented methods of generating netlists for use in post-layout simulation procedures. A lookup table includes a predetermined set of features (e.g., transistors of specified sizes and shapes) supported by an integrated circuit (IC) fabrication process, with dimensions and process induced dimension variations being included for each feature. A netlist is extracted from an IC layout, the extracted netlist specifying circuit elements (e.g., transistors) implemented by the IC layout and interconnections between the circuit elements. A search pattern is run on the IC layout to identify features in the IC layout corresponding to features included in the lookup table. Circuit elements in the extracted netlist that correspond to the identified features are then modified using values from the lookup table, and the modified netlist is output. In some embodiments, the netlist extraction, search pattern, and netlist modification are all performed as a single netlist generation step.

Abstract: Interconnecting logic provides connectivity of an embedded fixed logic circuit, or circuits, with programmable logic fabric of a programmable gate array such that the fixed logic circuit functions as an extension of the programmable logic fabric. The interconnecting logic includes interconnecting tiles and may further include interfacing logic. The interconnecting tiles provide selective connectivity between inputs and/or outputs of the fixed logic circuit and interconnect of the programmable logic fabric. The interfacing logic, when included, provides logic circuitry that conditions data transfers between the fixed logic circuit and the programmable logic fabric. In one operation, the programmable logic fabric is configured prior to the startup/boot sequence of the fixed logic circuit. In another operation, the fixed logic circuit is started up and is employed to configure the programmable logic fabric.

Abstract: Interconnecting logic provides connectivity of an embedded fixed logic circuit, or circuits, with programmable logic fabric of a programmable gate array such that the fixed logic circuit functions as an extension of the programmable logic fabric. The interconnecting logic includes interconnecting tiles and may further include interfacing logic. The interconnecting tiles provide selective connectivity between inputs and/or outputs of the fixed logic circuit and the interconnects of the programmable logic fabric. The interfacing logic, when included, provides logic circuitry that conditions data transfers between the fixed logic circuit and the programmable logic fabric.

Abstract: A PLD can be manufactured to include power supply lines from two sources so that a portion of the PLD can be backed up with a battery when power to the PLD is removed. A switch that supplies power to the backed up portion of the PLD receives power from both an external power supply and from the battery, and detects voltage level of the external power supply, switching to battery power when voltage from the external power supply is not sufficient.

Abstract: It is sometimes desirable to encrypt a design for loading into a PLD so that an attacker may not learn and copy the design as it is being copied into the PLD. According to the invention, the encrypted design is decrypted by a key or keys within the PLD that are preserved when power is removed by either being stored in nonvolatile memory or by being backed up with a battery that switches into operation when the power is removed from the PLD.

Abstract: The invention provides a structure and method of generating a clock enable signal in a programmable logic device (PLD). A first embodiment of the invention comprises a clock enable circuit implemented such that the critical paths have only two levels of logic. In this embodiment, the critical paths are implemented in dedicated logic while other portions of the clock enable circuit are implemented using programmable logic. According to another embodiment of the invention, the clock enable circuit is located near the center of a first edge of the device. A first plurality of output registers are located along the first edge on either side of the clock enable circuit, with additional output registers being located along the two adjacent half-edges. Programmable interconnection points (PIPs) permit a clock enable interconnect line along the first edge to be programmably extended to the additional output registers. In another embodiment, the clock enable circuit is duplicated in two opposite edges of the device.