Xilinx, Inc.

Lsi Corporation

Lsi Logic Corporation

Agere Systems Inc.

Mark J Marlett

Parag Upadhyaya

Mark David Rutherford

Khaldoon S Abugharbieh

Vassili Kireev

Adam Benjamin Healey

Michael O Jenkins

Peter John Windler

Toan D Tran

Cathy Ye Liu

Cheng Hsiang Hsieh

Philip N Jenkins

Jeff Kueng

John R Carrel

A termination circuit configured to provide electrostatic discharge (ESD) protection is provided. Termination sub-circuits are coupled in parallel, each including respective pull-up and pull-down circuits. Each pull-up circuit has two transistors of a first type coupled in series between a data input and Vdd, a gate of one of the two transistors being coupled to a control input and a gate of the other one of the two transistors being coupled to a first enable input of the termination sub-circuit. Each pull-down circuit has two transistors of a second type coupled in series between the data input and Vss or ground, a gate of one of the two transistors being coupled to the control input and the gate of the other one of the two transistors being coupled to a second enable input of the termination sub-circuit.

Front-end circuit with electro-static discharge protection

In accordance with some embodiments, an integrated circuit device comprises a circuit configured to provide a sense signal representing a dynamic power requirement of the circuit to a first sense node, a first sense switch coupled between the first sense node and a first die bump, and a sense switch controller configured to provide a control signal to the first sense switch.

Power supply regulation and optimization by multiple circuits sharing a single supply

An embodiment of an impedance adjustment apparatus is disclosed. For this embodiment of an impedance adjustment apparatus, a differential driver circuit has an input port, a first output port, a second output port, a first bias node, and a second bias node. A first impedance-voltage device is coupled to provide a first bias voltage to the first bias node. A second impedance-voltage device is coupled to provide a second bias voltage to the second bias node. A first analog voltage source is coupled to provide a first analog voltage to the first impedance-voltage device, and a second analog voltage source is coupled to provide a second analog voltage to the second impedance-voltage device.

Impedance tuning for termination

A symmetrical inductor includes an integrated circuit having a plurality of conductive layers. A first loop is disposed in an upper layer of the conductive layers, and at least two strapped loops are disposed in at least two layers of the conductive layers, respectively. The strapped loops are coupled in series to the first loop, and the at least two layers are below the upper layer. A second loop is disposed in the upper layer and is coupled in series to the at least two strapped loops. A first terminal electrode is coupled to the first loop, and a second terminal electrode is coupled to the second loop. A center-tap electrode is coupled to the at least two strapped loops.

Multiple-loop symmetrical inductor

In one embodiment of the invention, a voltage-mode line driver circuit is provided for transmitting a differential signal. The voltage-mode line driver includes a first voltage swing circuit having an input coupled to receive an input signal and an output coupled to a first transmission line. A second voltage swing circuit is included, the second voltage swing circuit having an input coupled to receive an inversion of the input signal and an output coupled to a second transmission line. First and second pre-emphasis circuits are respectively coupled to the first and second voltage swing circuits. The first and second pre-emphasis circuits are configured to supplement the slew rate of respective first and second voltage swing circuits in response to a transition of the input signal.

Voltage mode line driver and pre-emphasis circuit

An apparatus comprises a summer suitable for subtracting a filtered feedback signal from an input; a symbol decision device suitable for receiving an output from the summer; a feedback filter suitable for filtering an output from the symbol decision device and for sending the filtered feedback signal to the summer, the feedback filter comprising an adjustable swing amplifier and an adjustable pole filter; and an adaptation algorithm suitable for simultaneously adapting both a pole setting and a swing setting based upon a least mean squared error criteria. The summer, the symbol decision device, and the feedback filter form a feedback circuit utilized to reconstruct an electrical signal distorted during transmission.

Continuous time&#x2014;decision feedback equalizer

One embodiment of the present invention processes a signal of interest through an optional reference channel, combines the resulting signal with white noise, and then processes the noisy signal through a reference receiver. Two metrics are calculated from the results of that processing: Non-Compensable Data-Dependent Jitter (NC-DDJ) and Enhanced Transmitter and Waveform Dispersion Penalty (Enhanced TWDP). Within the reference receiver, a variable delay module sweeps the eye opening defined by the noise-free samples of the signal of interest and determines the transition points (i.e., edges) of the eye opening. Those transition points are compared to the Unit Interval to yield NC-DDJ. Further, the signal-to-noise ratio (SNR) of the noisy samples of the signal of interest is compared to the SNR of an ideal receiver (i.e., matched filter) driven by an ideal transmitter via an ideal channel with additive white Gaussian noise n(t) to yield Enhanced TWDP.

Characterizing non-compensable jitter in an electronic signal

A unit cell for a programmable termination circuit in an integrated circuit and a method for programming such termination circuit are described. In an embodiment, such unit cells may have three n-type and three p-type transistors. A first transistor is coupled to receive a first float control signal. A second transistor is coupled to receive a second float control signal. The third and fourth transistors are coupled to receive a first termination voltage control signal. The fifth and sixth transistors are coupled to receive a second termination voltage control signal. The first float control signal and the second float control signal are a pair of complementary signals.

Programmable termination

An improved method and apparatus for transmitting digital signals in a communications channel by compensating for distortions due to attenuation of high frequency components suffered by the digital signals. In a preferred embodiment, the digital signals are pulses and the compensation is performed at the transmitter without the need for an emphasis driver, by widening the pulses to compensate for the distortion in the channel that results in narrowing of the pulses incurred in the channel. The resulting pulse train is pre-compensated for the distortions caused by the communications channel. The amount of pre-compensation can be determined statically or dynamically.

System and method for transmit timing precompensation for a serial transmission communication channel

A continuous-time domain Decision Feedback Equalizer (DFE) for use in a serial communication channel comprises in one embodiment a summer, a decision circuit, a capture flip-flop (FF) and an N-th order active filter. The DFE and its active filter operate in continuous time to give improved performance over a discrete-time DFE. In one embodiment involving a first-order active filter, the capture FF is outside the continuous-time negative feedback loop of the DFE and involves a differential signal amplifier. In another embodiment, the capture flip-flop is inside the DFE loop, and in a third embodiment the decision circuit comprises a comparator.

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Livermore, CA, United States of America

Mark J Marlett