Abstract: A logic element includes memory elements, multiplexers, and controls. The multiplexers are arranged in levels including a highest level of multiplexers with inputs connected to the memory elements and outputs connected to inputs of a next-to-highest level of multiplexers and a first level of multiplexers with inputs connected to outputs of a second level of multiplexers and at least one output. The controls are connected to the multiplexers. In a first operational mode the controls determine a first-mode output at the at least one output of the first level of multiplexers, and in a second operational mode the controls determine a plurality of second-mode outputs at selected outputs of multiplexers not at the first level of multiplexers.

Abstract: Embodiments of N-well or P-well strap structures are disclosed with lower space requirements achieved by forming the strap on both sides of one or more floating polysilicon gate fingers.

Abstract: In accordance with one aspect of the invention, a hole is formed within an LE array of a PLD by interrupting the LE array base signal routing architecture such that a hole is left for IP function block to be incorporated. An interface region is provided for interfacing the remaining LE array base signal routing architecture to the IP function block.

Abstract: A programmable logic device (PLD) includes at least two regions. Each region includes electrical circuitry that has a set of transistors. Each of the two regions has a corresponding fixed transistor threshold voltage, a corresponding fixed transistor body bias, and a corresponding fixed supply voltage.

Abstract: The present invention provides a phase shift circuit that supports multiple frequency ranges. The phase shift circuit receives a plurality of control bits and causes a phase shift in a received signal, the phase shift corresponding to a number of time steps, the number depending on the control bits, and the time step is selected from a plurality of different time steps based on a frequency range associated with the received signal.

Abstract: Hardened programmable logic devices are provided with programmable circuitry. The programmable circuitry may be hardwired to implement a custom logic circuit. Generic fabrication masks may be used to form the programmable circuitry and may be used in manufacturing a product family of hardened programmable logic devices, each of which may implement a different custom logic circuit. Custom fabrication masks may be used to hardwire the programmable circuitry to implement a specific custom logic circuit. The programmable circuitry may be hardwired in such a way that signal timing characteristics of a hardened programmable logic device that implements a custom logic circuit may match the signal timing characteristics of a programmable logic device that implements the same custom logic circuit using configuration data.

Abstract: Error detection circuitry is provided on a programmable logic resource. Programmable logic resource configuration data is loaded into a cyclic redundancy check (CRC) module where a checksum calculation may be performed. In one embodiment, the checksum may be compared to an expected value, which is a precomputed checksum on data prior to being programmed into or while data is being programmed into a programmable logic resource. In another embodiment, the expected value may be included in the checksum calculation. An output indicating whether an error is detected may be generated depending on the relationship between the checksum and the expected value, or on the value of the checksum. This output may be sent to an output pin that is accessible by user logic.

Abstract: An integrated circuit having a logic element that includes an array of storage elements convertibly functioning as either a configuration random access memory (CRAM) or a static random access memory (SRAM) is provided. The logic element includes first and second pairs of data paths having dedicated multiplexers. In one embodiment, the first and second pairs of data paths are multiplexed into bit lines of a row of the array. The logic element also includes a data path control block generating control signals for each of the dedicated multiplexers. The control signals determine whether the storage elements function as a CRAM or a SRAM. A method for selectively configuring a memory array between a CRAM mode and SRAM mode are provided.

Abstract: Hardened programmable logic devices are provided with programmable circuitry. The programmable circuitry may be hardwired to implement a custom logic circuit. Generic fabrication masks may be used to form the programmable circuitry and may be used in manufacturing a product family of hardened programmable logic devices, each of which may implement a different custom logic circuit. Custom fabrication masks may be used to hardwire the programmable circuitry to implement a specific custom logic circuit. The programmable circuitry may be hardwired in such a way that signal timing characteristics of a hardened programmable logic device that implements a custom logic circuit may match the signal timing characteristics of a programmable logic device that implements the same custom logic circuit using configuration data.

Abstract: Hardened programmable logic devices are provided with programmable circuitry. The programmable circuitry may be hardwired to implement a custom logic circuit. Generic fabrication masks may be used to form the programmable circuitry and may be used in manufacturing a product family of hardened programmable logic devices, each of which may implement a different custom logic circuit. Custom fabrication masks may be used to hardwire the programmable circuitry to implement a specific custom logic circuit. The programmable circuitry may be hardwired in such a way that signal timing characteristics of a hardened programmable logic device that implements a custom logic circuit may match the signal timing characteristics of a programmable logic device that implements the same custom logic circuit using configuration data.

Abstract: An integrated circuit with memory elements is provided. The memory elements may have memory element transistors with body terminals. Body bias control circuitry may supply body bias voltages that strengthen or weaken memory element transistors to improve read and write margins. The body bias control circuitry may dynamically control body bias voltages so that time-varying body bias voltages are supplied to memory element transistors. Address transistors and latch transistors in the memory elements may be selectively strengthened and weakened. Process variations may be compensated by weakening fast transistors and strengthening slow transistors with body bias adjustments.

Abstract: Integrated circuits are provided with circuitry such as multiplexers that can be selectively configured to route different adjustable power supply voltages to different circuit blocks on the integrated circuits. The circuit blocks may contain memory elements that are powered by the power supply voltages and that provide corresponding static output control signals at magnitudes that are determined by the power supply voltages. The control signals from the memory elements may be applied to the gates of transistors in the circuit blocks. Logic on an integrated circuit may be powered at a given power supply voltage level. The memory elements may provide their output signals at overdrive voltage levels that are elevated with respect to the given power supply voltage level. Memory elements associated with circuit blocks that contain critical paths can be overdriven at voltages that are larger than memory elements associated with circuit blocks that contain noncritical paths.

Abstract: An integrated circuit having a logic element that includes an array of storage elements convertibly functioning as either a configuration random access memory (CRAM) or a static random access memory (SRAM) is provided. The logic element includes first and second pairs of data paths having dedicated multiplexers. In one embodiment, the first and second pairs of data paths are multiplexed into bit lines of a row of the array. The logic element also includes a data path control block generating control signals for each of the dedicated multiplexers. The control signals determine whether the storage elements function as a CRAM or a SRAM. A method for selectively configuring a memory array between a CRAM mode and SRAM mode are provided.

Abstract: The present invention provides a DQS bus for implementing high speed multiple-data-rate interface architectures in programmable logic devices. The DQS bus has a balanced tree structure between at least one data strobe circuit and a plurality of I/O register blocks.

Abstract: Integrated circuits such as programmable logic device integrated circuits are provided that have configuration random-access memory elements. The configuration random-access memory elements are loaded with configuration data to customize programmable logic on the integrated circuits. Each memory element has a capacitor that stores data for that memory element. A pair of cross-coupled inverters are connected to the capacitor. The inverters ensure that the memory elements produce output control signals with voltages than range from one power supply rail to another. Each configuration random-access memory element may have a clear transistor. The capacitor may be formed in a dielectric layer that lies above the transistors of the inverters, the address transistor, and the clear transistor. The inverters may be powered with an elevated power supply voltage.

Abstract: A programmable logic device (PLD) includes at least two regions. Each region includes electrical circuitry that has a set of transistors. Each of the two regions has a corresponding fixed transistor threshold voltage, a corresponding fixed transistor body bias, and a corresponding fixed supply voltage.

Abstract: The present invention provides a DQS bus for implementing high speed multiple-data-rate interface architectures in programmable logic devices. The DQS bus has a balanced tree structure between at least one data strobe circuit and a plurality of I/O register blocks.

Abstract: A programmable memory interface circuit includes a programmable DLL delay chain, a phase offset control circuit and a programmable DQS delay chain. The DLL delay chain uses a set of serially connected delay cells, a programmable switch, a phase detector and a digital counter to generate a coarse phase shift control setting. The coarse phase shift control setting is then used to pre-compute a static residual phase shift control setting or generate a dynamic residual phase shift control setting, one of which is chosen by the phase offset control circuit to be added to or subtracted from the coarse phase shift control setting to generate a fine phase shift control setting. The coarse and fine phase shift control settings work in concert to generate a phase-delayed DQS signal that is center-aligned to its associated DQ signals.

Abstract: Error detection circuitry is provided on a programmable logic resource. Programmable logic resource configuration data is loaded into a cyclic redundancy check (CRC) module where a checksum calculation may be performed. In one embodiment, the checksum may be compared to an expected value, which is a precomputed checksum on data prior to being programmed into or while data is being programmed into a programmable logic resource. In another embodiment, the expected value may be included in the checksum calculation. An output indicating whether an error is detected may be generated depending on the relationship between the checksum and the expected value, or on the value of the checksum. This output may be sent to an output pin that is accessible by user logic.

Abstract: There are provided methods and devices for providing overdrive voltages to address lines to help prevent leakage current in semiconductor memories, such as configuration memories used with programmable logic devices. Specifically, for example, there is provided a memory that includes an array of memory cells. Each memory cell includes a retainer circuit. An access transistor is coupled to the retainer circuit. An overdrive voltage level may be applied to the access transistor.