Abstract:
A method for performing timing analysis on calibrated paths includes performing static timing analysis on the calibrated paths to obtain delay and margin information. The delay and margin information are utilized to emulate operations performed during calibration.
Abstract:
A method for designing a system on a target device includes identifying candidate portions in the system to preserve based on similarities between the system and another system. Preservation criteria are applied on the candidate portions in the system to preserve to identify portions of the system to preserve. Design results from the another system are reused for portions in the system that are preserved.
Abstract:
Clock switch-over circuits and methods provide clock signals to clock routing networks. According to one embodiment, a multiplexer selects between a first clock signal and a second clock signal in response to a switch select signal received from a control circuit. A storage circuit stores an enable signal in response to an output clock signal of the multiplexer. A logic circuit transmits the output clock signal of the multiplexer to a clock routing network in response to the enable signal from the storage circuit. At least one signal is transmitted from the clock switch-over circuit to the control circuit.
Abstract:
A source-synchronous capture unit includes a data register unit to register data synchronized to a strobe or non-free running clock. The source synchronous capture unit also includes an asynchronous first-in-first-out (FIFO) unit to store the data from the data register unit in response to the strobe or non-free running clock and to output the data stored, in response to another clock.
Abstract:
An integrated circuit (IC) includes a set of metastability-hardened storage circuits. Each metastability-hardened storage circuit may include: (a) a pulse width distortion circuit; (b) a first circuit powered by a nominal power supply voltage, and a second circuit powered by a higher-than-nominal supply voltage; (c) an inverter and a bias circuit, where the bias circuit provides a bias current based on an intermediate state of the inverter to resolve a metastable state of the inverter; or (d) a latch, and a dynamic bias circuit that causes current to be injected into the latch to resolve a metastable state of the latch.
Abstract:
A method for connecting a first and second component in a logic device is disclosed. A path is generated between the first and second components with an appropriate amount of delay to satisfy short-path timing constraints that define a minimum delay on the path. A first interconnect line from a plurality of interconnect lines and a second interconnect line to connect with the first interconnect line sub-optimally from a delay minimization perspective are selected in order to satisfy the short-path timing constraints.
Abstract:
A method for designing a system on a target device having restricted areas includes determining locations on the target device for all cells in the system by solving one or more equations. Partitioning of cells of a first classification type is performed. One or more equations are modified in response to the partitioning. Revised locations on the target device are determined for the cells by solving the modified one or more equations. The partitioning procedure takes into consideration the classification types of cells as well as restricted areas on the target device.
Abstract:
Circuits, methods, and apparatus for delaying signals in a power and area efficient manner are provided. A gating element within a stage of a programmable delay element suppresses an operation of other stages of the delay element. A programmable delay has components with differing delays that may be combined to give flexibility in choices for delay increments while minimizing the area of the delay element. A delay element is shared between different signal paths, for example, to reduce the number of delay elements or to allow utilizing unused delay elements of other signal paths.
Abstract:
A method for designing a system on a target device includes performing timing analysis at an intermediate node on a data path from a source to a destination to determine whether rise and fall skew of components on the data path could result in data not being sampled at the destination.
Abstract:
A source-synchronous capture unit on a receiving circuit includes a first first-in-first-out (FIFO) unit operable to synchronize a write enable signal to generate a synchronized write enable signal that is synchronized with a first free running clock associated with a memory external to the receiving circuit. The write enable sign is generated in response to a read operation by the receiving circuit. The source-synchronous capture unit also includes a second FIFO unit operable to store data from the memory in response to the first free running clock and the synchronized write enable signal, and to output the data in response to a second free running clock associated with the receiving circuit and a read enable signal.