Xilinx, Inc.

Advanced Micro Devices Corporation

Qualcomm Incorporated

Legerity, Inc.

Michael A Nix

Ahmed Younis

Brian Taylor Brunn

John G Bartkowiak

Moises Emanuel Robinson

Jinghui Lu

Shahriar Rokhsaz

Carlin D Cabler

Stephen D Anderson

Michael Ren Kent

Stephen Victor Kosonocky

Safdar M Asghar

David Erich Tetzlaff

Sebastien Nussbaum

Firas Najeh Abughazaleh

Xiaojie He

Golam Rasul Chowdhury

Walter Stuart Schopfer

Sonu Arora

Anil Kumar

Sergio R Ramirez

Saeed Abbasi

Faisal A Syed

Jeffrey Jay Anderson

Curtis M Brody

Yvette P Lee

Thomas Hirsch

Imran Baqai

Ahmed Abdell-Ra'oof Younis

Clayton D English

Leonard Disanza

Kazi S Hossain

Mingdeng Chen

A technique for adjusting a power supply for a device is provided. The technique includes detecting a low-power trigger for a device; switching a power supply for the device from a high-power power supply to a low-power power supply; detecting a high-power trigger for a device; and switching a power supply for the device from the low-power power supply to the high-power power supply, wherein the high-power power supply consumes a larger amount of power than the low-power power supply, and wherein the high-power power supply provides a greater amount of noise reducing and a greater tolerance to temperature differences than the low-power power supply.

Power delivery system having low- and high-power power supplies

Apparatus and method are disclosed for measuring a load current supplied to one or more integrated circuit cores. The apparatus includes a power gating field effect transistor (FET) comprising a gate, a source, and a drain, wherein the source is coupled to a voltage rail, wherein the drain is coupled to a load, and wherein the gate is configured to receive a gating voltage to selectively turn on the power gating FET to allow a load current to flow between the voltage rail and the load; and a differential amplifier configured to generate a current-related voltage related to the load current by applying a gain to an input voltage based on a drain-to-source voltage of the power gating FET, wherein the gain varies inversely with the input voltage in response to variation in temperature or gate-to-source voltage of the power gating FET.

Apparatus and method for measuring load current by applying compensated gain to voltage derived from drain-to-source voltage of power gating device

A high voltage protection circuit for a non-tolerant integrated circuit is described herein. A non-tolerant integrated circuit may be a powered down integrated circuit or a low voltage tolerant integrated circuit, that may be exposed to a high voltage source such as an external circuit, device or power supply. The high voltage protection circuit includes a limiting transistor circuit, a control transistor circuit, and an isolation transistor circuit. The limiting transistor circuit limits or holds the voltage at the signal bump to be less than a voltage that can damage the circuit. The isolation transistor circuit disconnects input/output signal circuitry from normal protection circuitry. Both the limiting transistor circuit and the isolation transistor circuit are controlled by the control transistor circuit and are responsive to the power supply voltage being off.

High voltage protection circuit for non-tolerant integrated circuit

A method and apparatus is provided for monitoring performance of an processor to detect tampering and place the processor in a safe operating state that prevents unauthorized access to contents of the processor. In one example, the method and apparatus compares a measured value of an operating parameter (i.e., a temperature, supply voltage or clock signal) to predefined limits to identify an out of limits measured value. If an out of limits measured value is detected during a normal operating mode, the processor enters a reset mode, and if an out of limits measured value is detected during power up or reset, the processor in retained a reset mode.

Method and apparatus for monitoring performance for secure chip operation

A power-up control circuit utilizes on-chip circuits, multiple voltages, a ring oscillator and counter, and edge and level detection circuits to guarantee reset during power-up conditions and continues the reset state with a variable length counter to guarantee a predictable reset. In addition, a clean start-up after a logical power-down condition is provided.

On-chip power-up control circuit

A 1.5-bit algorithmic analog-to-digital converter (ADC) generates a digital value representative of an input voltage. The ADC implements a series of conversion cycles for a conversion operation. Each conversion cycle has three sub-cycles: a scaling sub-cycle, a first sample sub-cycle, and a second sample sub-cycle. In the scaling sub-cycle, the residual voltage from the previous conversion cycle is doubled to generate a first voltage. In the first sample sub-cycle, a first bit of a corresponding bit pair is determined based on the polarity of the first voltage. The first voltage is either increased or decreased by a reference voltage based on the polarity of the first voltage to generate a second voltage. In the second sample sub-cycle, a second bit of the corresponding bit pair is determined based on the polarity of the second voltage. The second voltage then is either increased or decreased by the reference voltage based on the polarity of the second voltage to generate the residual voltage used for the next conversion cycle in the series. Each bit pair is mapped to a corresponding two-bit code value and the resulting code values are used to generate the digital value.

Algorithmic analog-to-digital conversion

A method and apparatus for advantageously utilizing the reset state of an RTZ shift register to guarantee proper data alignment at the feedback taps to facilitate decision feedback equalization (DFE) in a unified signaling system. An input data stream is sliced into an even data stream and an odd data stream, whereby the sliced data is compared to a programmable threshold depending upon a detection mode. Each bit of the even data stream is propagated through RTZ latches and each bit of the odd data stream is propagated through RTZ latches. At any given instant in time, a correct portion of the RTZ latch outputs contain zero information, so that each latch output may be summed in a current mode without the need for any intervening logic. The input data stream is summed in current mode with the feedback data and converted to voltage prior to sampling the currently received data bit.

Method and apparatus for a unified signaling decision feedback equalizer

An oscillator. The oscillator includes a first ring oscillator having a first plurality of inverters, a first plurality of capacitors each having a first terminal coupled to an output terminal of a corresponding one of the first plurality of inverters, a second ring oscillator having a second plurality of inverters, and a second plurality of capacitors each having a first terminal coupled to an output terminal of a corresponding one of the second plurality of inverters. A second terminal of the first plurality of capacitors is coupled to an output terminal of a corresponding one of the second plurality of inverters. A second terminal of the second plurality of capacitors is coupled to an output terminal of a corresponding one of the first plurality of inverters. The oscillator is configured to provide as an output a differential clock signal.

Complementary ring oscillator with capacitive coupling

A communication system includes a transmitter, a communication channel, and a receiver. The transmitter includes a pre-emphasis module, a summing module, a line driver, and a decision feedback pre-emphasis (DFP) module to produce a pre-emphasized serial stream of data based on a communications channel response and an inter-symbol interference level. The receiver includes a linear equalizer, a summing module, a decision module, and a decision feedback equalization (DFE) module. The linear equalizer produces an equalized serial stream of data. The summing module sums at least one data element of the equalized serial stream of data with DFE data elements to produce equalized data elements. The decision module interprets the equalized data elements to produce interpreted data elements to DFE module, which produces the DFE data elements from the interpreted data elements.

Combined decision feedback equalization and linear equalization

A method and apparatus for combining an alternating current (AC) coupling technique with a low frequency restoration technique to provide AC coupling with low frequency restoration of the attenuated low frequency content. The low frequency restoration circuit operates to extract low frequency information prior to being high-pass filtered by the AC coupling circuit. The low frequency restoration circuit then buffers the low frequency information through a low frequency restoration amplifier, applies a programmable common mode voltage to the buffered, low frequency information, and then restores the buffered, common mode adjusted, low frequency information to the output of the AC coupling circuit.

Method and apparatus for a direct current (DC) coupled input buffer

An example embodiment is directed to an arrangement and method for phase-aligning digital data to be sent by transmit-data modules over respectively-situated serial links. A reference clock signal is communicatively coupled to each transmit-data module, each transmit-data module having a data driver and a clock circuit. At the serial links, each respective data driver sends digital data in response to a clock-output signal and a phase-adjusted clock-load signal that is used to load the data driver. The phase of the clock-load signal is adjusted relative to misalignment between the clock-load signal and the reference clock signal so that each data driver loads the digital data in a time-aligned manner for link transmission. The present invention is useful in applications involving programmable logic devices and other skew-susceptible parallel transmission arrangements.

Approach for adjusting the phase of channel-bonded data

An example embodiment is directed to shifting the common mode voltage of an analog oscillation stage toward a center line between the upper and lower power-supply rails of a first digital circuit. The first digital circuit has a digital input port adapted to respond to signal transitions defined between the supply rails, and the analog oscillation stage generates an oscillating analog signal that has a common-mode voltage that is not centered between the upper and lower power-supply rails. The oscillating analog signal, which drives the digital input port, changes alternately with the phases of the oscillating analog signal. To shift the common mode voltage of an analog oscillation stage toward the center line between the rails, a feedback circuit generates a contending digital signal that drives the digital input port with alternating states as defined by opposite phases.

Circuit approach for common mode control in high-frequency clocks

A decision feedback equalization ('DFE') technique is suitable for use in a serializer-deserializer ('SERDES') receiver in an integrated circuit (IC). The IC has a summing node coupled to a return-to-zero (&#x201c;RTZ&#x201d;) data latch register. The RTZ data latch register has a first (&#x201c;even&#x201d;) series of RTZ data latches and a second (&#x201c;odd&#x201d;) series of RTZ data latches. A first even tap is coupled to the first even RTZ data latch and provides a feedback signal to the summing node on a first portion of a local clock cycle. A first odd tap is coupled to the first odd RTZ data latch and provides an odd feedback signal to the summing node on a second portion of the local clock cycle.

Decision-feedback equalization clocking apparatus and method

A limiting circuit includes an input transconductance stage, an output transconductance stage, a feedback transconductance stage, first and second resistive loads, and a level limiting circuit. The input transconductance stage is operably coupled to convert an input voltage signal into an input current signal. The first resistive load is operably coupled to convert the input current signal and a feedback current signal into an intermediate output voltage signal. The output transconductance stage is operably coupled to convert the intermediate output voltage signal into an output current signal. The second resistive load is operably coupled to convert the output current signal into an output voltage signal. The feedback transconductance stage is operably coupled to produce the feedback current signal based on the output voltage signal. The level limiting module is operably coupled to limit at least one voltage level of the feedback transconductance stage.

Limiting circuit with level limited feedback

A differential flip-flop () has an output stage () with first and second input terminals (X, X), first and second output terminals (Q, Qb), a first voltage supply terminal (Vss), a first transistor () having a first current-handling terminal connected to the first output terminal (Q), a second current-handling terminal connected to the second output terminal (Qb), and a first control terminal connected to a clock signal (C). A second transistor has a third current-handling terminal connected to the first output terminal (Q), a fourth current-handling terminal connected to the voltage supply terminal (Vss), and a second control terminal connected to a first input terminal (X) of the output stage. A third transistor () has a fifth current-handling terminal connected to the first output terminal (Q), a sixth current-handling terminal connected to the voltage supply terminal (Vss), and a third control terminal connected to the second output terminal (Qb).

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Buda, TX, United States of America

Michael A Nix