Abstract:
An integrated circuit includes physical media attachment ("PMA") circuitry that includes two different kinds of transceiver channels for serial data 5 signals. One kind of transceiver channel is adapted for transceiving relatively low-speed serial data signals. The other kind of transceiver channel is adapted for transceiving relatively high-speed serial data signals. A high-speed channel is alternatively 10 usable as phase-locked loop ("PLL") circuitry for providing a clock signal for use by other high- and/or low-speed channels. A low-speed channel can alternatively get a clock signal from separate low-speed PLL circuitry.
Abstract:
A link simulation tool for simulating high-speed communications link systems is provided. Communications links may include link subsystems such as transmit (TX) circuitry, receive (TX) circuitry, oscillator circuits that provide reference clock signals to the TX and RX circuitry, and channels that link the TX and RX circuitry. The link simulation tool may model each of the subsystems using behavioral models. The behavioral models may include characteristic functions such as transfer functions, probability density functions, and eye characteristics. The link simulation tool may have a link analysis engine that is capable of performing two- dimensional (two-variable) convolution operations and in applying dual-domain (frequency-time) transformations on the characteristic functions provided by the behavioral models to simulate the performance of the link system. The link simulation tool may have an input screen that allows a user to specify desired link parameters and a data display screen that display simulated results.
Abstract:
An oscillator circuit includes transistors that are cross-coupled through routing conductors in a first conductive layer. The oscillator circuit also includes a varactor, a capacitor, and an option conductor in a second conductive layer. The option conductor forms at least a portion of a connection between one of the transistors and the capacitor or the varactor.
Abstract:
A programmable logic device package comprising: a package (64); a solder ball (66) positioned on a first surface of said package, said solder ball located for receiving an external signal, a plurality of signal interface bumps (62) positioned on a second surface of the package, and a set of routing leads (68) extending through said package and connecting said solder ball to each of the plurality of signal interface bumps, wherein said set of routing leads distribute said external signal to said signal interface bumps.
Abstract:
An integrated circuit ("IC") may include circuitry for use in testing a serial data signal. The IC may include circuitry for transmitting the serial data signal with optional jitter, optional noise, and/or controllably variable drive strength. The IC may also include circuitry for receiving the serial data signal and performing a bit error rate ("BER") analysis in such a signal. The IC may provide output signals indicative of results of its operations. The IC can operate in various modes to perform or at least emulate functions of an oscilloscope, a bit error rate tester, etc., for testing signals and circuitry with respect to jitter-tolerance, noise-tolerance, etc.
Abstract:
Integrated circuits with phase-locked loops are provided. Phase-locked loops may include an oscillator, a phase-frequency detector, a charge pump, a loop filter, a voltage-controlled oscillator, and a programmable divider. The voltage-controlled oscillator may include multiple inductors, an oscillator circuit, and a buffer circuit. A selected one of the multiple inductors may be actively coupled to the oscillator circuit. The voltage-controlled oscillators may have multiple oscillator circuits. Each oscillator circuit may be coupled to a respective inductor, may include a varactor, and may be powered by a respective voltage regulator. Each oscillator circuit may be coupled to a respective input transistor air in the buffer circuit through associated coupling capacitors. A selected one of the oscillator circuits may be turned on during normal operation by supplying a high voltage to the selected one of the oscillator circuit and by supply a ground voltage to the remaining oscillator circuits.
Abstract:
A circuit includes a first area, a second area, and a third area. The second area includes a locked loop circuit that generates a clock signal. The locked loop circuit receives a supply voltage that is isolated from noise generated in the first area. The third area includes multiple quads of channels and a clock line coupled to route at least one clock signal generated in the second area to the channels in each of the quads. The third area is separate from the second area in the circuit.
Abstract:
Circuitry for receiving a serial data signal (e.g., a high-speed serial data signal) includes adjustable equalizer circuitry for producing an equalized version of the serial data signal. The equalizer circuitry may include controllably variable DC gain and controllably variable AC gain. The circuitry may further include eye height and eye width monitor circuitry for respectively producing first and second output signals indicative of the height and width of the eye of the equalized version. The first output signal may be used in control of the DC gain of the equalizer circuitry, and the second output signal may be used in control of the AC gain of the equalizer circuitry.
Abstract:
An integrated circuit (e.g., a programmable integrated circuit such as a programmable microcontroller, a programmable logic device, etc.) includes programmable circuitry and 10 Gigabit Ethernet (10GbE) transceiver circuitry. The programmable circuitry and the transceiver circuitry may be configured to implement the physical (PHY) layer of the 10GbE networking specification. This integrated circuit may then be coupled to an optical transceiver module in order to transmit and receive 10GbE optical signals. The transceiver circuitry and interface circuitry that connects the transceiver circuitry with the programmable circuitry may be hard-wired or partially hard-wired.
Abstract:
Techniques for providing high-performance interconnect for integrated circuits will improve overall integrated circuit performance. These techniques include arranging, laying out, and fabricating the signal conductors (e.g., 405, 720) so the parasitic coupling capacitances (e.g., 425) are minimized and parasitic resistance is reduced. The techniques will minimize effects of crosstalk noise between the conductors, and thus improve overall integrated circuit performance.