Abstract: In one embodiment, an integrated circuit (IC) is presented. The IC includes first and second sets of power distribution lines formed in the IC. The IC includes first and second capacitors formed in one or more layers of the IC. A first plurality of vias couple a first input of the first and second capacitors to the first set of power distribution lines, and a second plurality of vias couple a second input of the first and second capacitors to the second set of power distribution lines. The first capacitor and the first plurality of vias and the second plurality of vias coupled thereto having an equivalent series resistance greater than an equivalent series resistance of the second capacitor and the first plurality of vias and the second plurality of vias coupled thereto.

Abstract: In one embodiment, an integrated circuit (IC) is presented. The IC includes first and second sets of power distribution lines formed in the IC. The IC includes first and second capacitors formed in one or more layers of the IC. A first plurality of vias couple a first input of the first and second capacitors to the first set of power distribution lines, and a second plurality of vias couple a second input of the first and second capacitors to the second set of power distribution lines. The first capacitor and the first plurality of vias and the second plurality of vias coupled thereto having an equivalent series resistance greater than an equivalent series resistance of the second capacitor and the first plurality of vias and the second plurality of vias coupled thereto.

Abstract: A circuit has a programmable mode control section, and a receiver section with first and second input terminals and an output terminal. The method and apparatus involve setting the mode control section to one of first and second states in response to user input, and operating the receiver section in first and second operational mode when the mode control section respectively has the first and second states, wherein in the first operational mode the receiver section provides higher performance and consumes more power than in the second operational mode.

Abstract: A clock distribution network having: a backbone clock signal line configured to provide a differential clock signal; multiple branches coupled to the backbone clock signal line for distributing the differential clock signal to multiple programmable function elements; a first leaf node coupled to a first branch, where the first leaf node is configured to provide the differential clock signal to a first programmable function element; and a second leaf node coupled to a second branch, where the second leaf node is configured to provide a single ended clock signal derived from the differential clock signal to a second programmable function element.

Abstract: Signal distribution of a regional signal is described. An integrated circuit 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: A data alignment and deskewing module includes a delay calibration unit, a data alignment and deskew unit, and a delay unit. The delay calibration unit is operably coupled to generate a reference signal based on a reference clock and a mirrored delay line output signal. The data alignment and deskew unit is operably coupled to determine a delay selection signal based on a delayed and deskewed representation of an input data stream and propagation delay of a line on which the input data stream is received. The delay unit is operably coupled to produce the delayed and deskewed representation of the input data stream based on the reference signal and the delay selection signal.

Abstract: A clock distribution network having: a main trunk configured to provide a differential clock signal; a plurality of branches coupled to the main trunk for distributing the differential clock signal to a plurality of circuit elements on the integrated circuit; and a plurality of switches coupling the main trunk to the plurality of branches.

Abstract: A clock distribution network having: a backbone clock signal line configured to provide a differential clock signal; multiple branches coupled to the backbone clock signal line for distributing the differential clock signal to multiple programmable function elements; a first leaf node coupled to a first branch, where the first leaf node is configured to provide the differential clock signal to a first programmable function element; and a second leaf node coupled to a second branch, where the second leaf node is configured to provide a single ended clock signal derived from the differential clock signal to a second programmable function element.

Abstract: A clock distribution network having: a main trunk configured to provide a differential clock signal; a plurality of branches coupled to the main trunk for distributing the differential clock signal to a plurality of circuit elements on the integrated circuit; and a plurality of switches coupling the main trunk to the plurality of branches.

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: One or more configurable transceivers can be fabricated on an integrated circuit. The transceivers contain various components having options that can be configured by turning configuration memory cells on or off. The integrated circuit may also contain programmable fabric. Other components in the transceivers can have options that are controlled by the programmable fabric. The integrated circuit may also contain one or more processor cores. The processor core and the transceivers can be connected by a plurality of signal paths that pass through the programmable fabric.

Abstract: A system for distributing a small signal differential signal to a circuit element. The system includes: a first converter configured to convert a first small signal differential signal to a first two phase full CMOS differential signal for input into the differential multiplexer; and a programmable driver circuit configured to boost an output current of the programmable driver circuit at selected frequencies and to convert two phase full CMOS differential signal outputs of the differential multiplexer to a second small signal differential signal.

Abstract: A clock distribution network having: a main trunk configured to provide a differential clock signal; a plurality of branches coupled to the main trunk for distributing the differential clock signal to a plurality of circuit elements on the integrated circuit; and a plurality of switches coupling the main trunk to the plurality of branches.

Abstract: A clock distribution network having: a backbone clock signal line configured to provide a differential clock signal; multiple branches coupled to the backbone clock signal line for distributing the differential clock signal to multiple programmable function elements; a first leaf node coupled to a first branch, where the first leaf node is configured to provide the differential clock signal to a first programmable function element; and a second leaf node coupled to a second branch, where the second leaf node is configured to provide a single ended clock signal derived from the differential clock signal to a second programmable function element.

Abstract: Disclosed are methods and structures for preparing data for transmission over a network. In an embodiment consistent with the OSI network model, transmit and receive CRC generators are moved from the link layer to the physical layer, which frees up valuable programmable logic resources when a programmable logic device is employed to perform the functions of the link layer. The CRC generators of the physical layer comply with a plurality of network communication standards.

Abstract: An elastic buffer for buffering a stream of data blocks includes a controller and a memory space, wherein multiple data blocks can be written and read during a single write or read clock cycle, respectively. Multiple read addresses are used for each read operation, allowing read access to non-contiguous memory locations during a single read cycle when desired. Therefore, the elastic buffer can perform clock correction and channel bonding operations on data streams that include correction and alignment data block sequences that do not match the width of the memory space. A stagger bit can be used to indicate the timing of read address adjustments during clock correction and channel bonding operations.

Abstract: A system for driving a differential signal on a signal line and converting the differential signal from a rail-to-rail differential signal to a small signal differential signal is described. An exemplary embodiment of the circuit includes a first programmable differential driver circuit receiving a differential input; a programmable delay circuit receiving the differential input and coupled to a second programmable differential driver circuit; and a summation circuit coupled to the first and second differential driver circuits.

Abstract: A configurable low voltage differential signal (LVDS) system is located on a chip, such as a programmable logic device. The configurable LVDS system includes a pair of I/O pads, an LVDS transmitter for driving a differential output signal onto the I/O pads, an LVDS receiver for receiving a differential input signal from the I/O pads, and a termination resistor coupled across the pair of I/O pads, wherein the termination resistance can be enabled for use with either the LVDS transmitter or the LVDS receiver. Control circuitry is provided to control the selective enabling and disabling of the LVDS transmitter, the LVDS receiver and the termination resistance. This control circuitry can be configured in response to configuration data values stored on the chip.

Abstract: A transmit variable-width interface can be programmed to convert an electronic digital data path that is either 1N, 2N, 4N, or 8N bits wide into a data path that is 2N bits wide, either by serializing bits (4N- or 8N-bit cases), re-clocking bits (2N-bit case), or grouping bits (1N-bit case). A receive variable-width interface can be programmed to convert a data path 2N bits wide into a data path that is 1N, 2N, 4N, or 8N bits wide. The widths of the two variable-width data paths are controlled independently. The variable-width interfaces are coupled between a multi-gigabit transceiver and core logic of a programmable logic device. The incoming and outgoing data paths of the variable-width interfaces have separate clocks signals that are synchronized such that small amounts of skew in these clock signals do not disrupt the operation of the variable-width interfaces.

Abstract: A programmable logic device (PLD) is provided that supports multi-gigabit transceivers (MGTs). The PLD includes one or more pairs of shared clock pads for receiving one or more high-quality differential clock signals. Dedicated clock traces couple each pair of shared clock pads to one or more MGTs on the PLD. Each MGT includes a clock multiplexer circuit, which allows one of the high-quality differential clock signals to be routed as a reference clock signal for the MGT. The clock multiplexer circuits are designed such that no significant jitter is added to the high-quality clock signals. The clock multiplexer circuits can also route general-purpose clock signals received by the PLD as lower quality reference clock signals for the MGTs. The reference clock signal routed by the clock multiplexer circuit can be stepped down to provide a reference clock for a physical coding sublayer of the MGT.