Xilinx, Inc.

Nxp Usa, Inc.

Freescale Semiconductor,inc.

Other

Advanced Micro Devices Corporation

Legerity, Inc.

Firas Najeh Abughazaleh

Brian Taylor Brunn

Sanjay Kumar Wadhwa

David R Bearden

Ahmed Younis

Anand Kumar Sinha

Vijayakumaran Velayudhan Nair

Devesh P Singh

Shahriar Rokhsaz

Michael A Nix

Moises Emanuel Robinson

James Andrew Welker

Jinghui Lu

Stephen D Anderson

Merle L Miller

Venkataram Mooraka

Michael Ren Kent

Yvette P Lee

Tommi Jorma Mikael Jokinen

Michael Edward Stibila

Roby Thomas

Kazi S Hossain

Venkata Rama Mohan Reddy Mooraka

Venkatarama Mohanareddy Mooraka

An apparatus is disclosed that includes a phase detector circuit for generating a first pulse signal based on first and second input clock signals. A first circuit adjusts the first pulse signal by delaying transmission of a leading edge of the first pulse signal, but not a trailing edge of the first pulse signal. A charge pump circuit charges or discharges a capacitor based on the adjusted first pulse signal, and a voltage controlled oscillator (VCO) circuit generates an output clock signal with a frequency that depends on a voltage on the capacitor.

Fractional N PLL with sigma-delta noise cancellation

A phase to digital converter (PDC) generates a digital output that represents a phase difference between first and second clocks. The PDC includes a gated ring oscillator (GRO), which includes N signal delay elements coupled together in a ring via a logic gate, wherein a 1st signal delay element of the ring comprises an input coupled to an output of the logic gate, and wherein a Nth signal delay element of the ring comprises an output coupled to a first input of the logic gate. A convertor is coupled to the GRO and configured to generate low order bits of the digital output based on outputs of the logic gate and the N signal delay elements. A first counter includes an input coupled to an output of one of the N signal delay elements or the logic gate, wherein the first counter is configured to generate a first digital counter value. A second counter includes an input coupled to an output of another one of the N signal delay elements or the logic gate, wherein the second counter is configured to generate a second digital counter value. The PDC generates the digital output signal based on the low order bits and one of the first and second digital counter values.

Phase to digital converter

An on-chip temperature sensor generates a proportional to absolute temperature current and sloped bandgap reference current with transistor offset cancelled using chopping circuitry and dynamic element matching circuitry with resistor-based current mirrors. A digital successive approximation register (SAR) code provided to a digital to analog converter (DAC) is adjusted until current output by the DAC matches the PTAT current.

Temperature sensor circuitry and method therefor

An integrated circuit die that includes a temperature monitoring system that obtains measured temperature data from on die temperature sensors during a mode when power is not being supplied to a system controller of the die. After the system controller is powered up, the system controller obtains the measured temperature data. This system and method can be useful in that heat from a powered up system controller does not affect the temperature readings of the temperature monitoring system.

Thermal monitoring system in an integrated circuit die

A semiconductor device includes an operational transconductance amplifier (OTA) with a matched pair of transistors including a first transistor and a second transistor, and configuration units that include a first set of switches, a second set of switches, and an input transistor. Gain adjustment circuitry is coupled to adjust gain of the OTA. Measurement circuitry is coupled to measure offset in the OTA. Control logic is configured to operate the first and second sets of switches to couple input transistors of a first group of the configuration units to the first transistor of the matched pair of transistors, and to couple input transistors of a remaining group of the configuration units to the second transistor of the matched pair of transistors. Settings of the first and second sets of switches are selected to minimize the offset.

Operation amplifiers with offset cancellation

A duty cycle correction circuit has a delay line comprising a plurality of current-starved inverters coupled together in series. An input of a first current-starved inverter receives an input clock signal. A relatively weak inverter is coupled in parallel with each of the current-starved inverters. A low pass filter having an operational amplifier has a differential input coupled to the output of the delay line for receiving an output clock signal. A single-ended output of the operational amplifier is coupled to current source and current sink transistors of each of the current-starved inverters to control the amount of delay provided by the delay line. The low pass filter corrects the duty cycle of the input clock signal so that the output clock signal has a 50 percent duty cycle. The relatively weak parallel-connected inverters insure that no clock pulses are skipped if the current-starved inverters fail to transition.

Bounded duty cycle correction circuit

A charge pump includes a charge pump core circuit, a replica bias circuit, and a differential amplifier. The charge pump core circuit includes current source and sink circuits for charging and discharging an output node of the charge pump core circuit. The current source and current sink circuits are user programmable using bit signals to adjust a bandwidth and a phase margin of a phase-locked loop (PLL) that includes the charge pump. An impedance of the replica bias circuit varies based on the bit signals. The differential amplifier and the replica bias circuit form a feedback loop that reduces current mismatch between the current source and sink circuits.

Programmable charge pump

A phase-locked loop (PLL) for generating an oscillating signal includes a frequency bounding circuit. When a frequency of the oscillating signal is greater than a first threshold value, which is greater than a maximum normal operational frequency of the PLL, the frequency bounding circuit forces a charge pump to discharge a loop filter until the oscillating signal frequency is less than a second threshold value that is within the normal operational frequency range of the PLL. When the frequency of the oscillating signal is less than a third threshold value, which is less than a minimum normal operational frequency of the PLL, the frequency bounding circuit forces the charge pump to charge the loop filter until the oscillating signal frequency is greater than a fourth threshold value that is within the normal operational frequency range of the PLL.

Phase-locked loop with frequency bounding circuit

A lawn rake or lawn rake attachment provides a capture structure which cooperates with the tines of a lawn rake to increase the collection of small leaves and debris with each stroke of the rake. More specifically, the capture structure provides a broad surface preferably spanning the width of the rake and positioned an effective distance trailing behind the rake tine structure. In operation of the lawn rake equipped with the capture structure, during the course of a stroke of the rake the rake tines stir up the small leaves in or on the lawn grass. The stirring-up action propels the leaves a distance up above the ground before they fall back on the rake stroke trail. The trailing rake capture structure intercepts the airborne leaves and holds them at its surface while the rake is in a forward raking motion.

Lawn rake attachment and lawn rake for small debris

A method and apparatus for reducing parasitic capacitance. A P-well blocked layer is formed directly beneath a parasitic device. The P-well blocked layer significantly increases the resistance underneath the parasitic device. The resistance of the P-well blocked layer, in effect, partially disconnects the parasitic device from the ground terminal to minimize the effective capacitive impedance that is added to the total termination impedance.

Method and apparatus for reducing parasitic capacitance

An integrated circuit includes a substrate, a noise sensitive circuit, and a first low impedance guard ring. The substrate includes a well-doped blocking ring that at least partially surrounds the noise sensitive circuit. The noise sensitive circuit is fabricated on the substrate. The first low impedance guard ring is fabricated on the substrate to at least partially surround the well-doped blocking ring, wherein the first low impedance guard ring is operably coupled to a first circuit ground, wherein impedance of the first low impedance guard ring is substantially less than impedance of the well-doped blocking ring.

Substrate coupled noise isolation for integrated circuits

A clock and data recovery circuit includes even and odd latches, a detection module, a clock recovery module, a compensating module, and a data recovery module. The even and odd latches are operably coupled to latch even and odd bits of a digital stream of data based on a recovered clock to produce even and odd latched bits. The detection module is operably coupled to produce a phase representative pulse stream based on the even and odd latched bits. The clock recovery module is operably coupled to produce the recovered clock based on the phase representative pulse stream. The compensating module is operably coupled to adjust biasing of the even and odd latches based on operating parameter changes of the clock and data recovery circuit. The data recovery module is operably coupled to produce recovered data from the even and odd latched bits based on the recovered clock.

Clock and data recovery circuit having operating parameter compensation circuitry

The multi-mode phase and data detector includes a phase detector and a charge pump. A plurality of latching blocks clocked on complimentary phases of a feedback signal produces a plurality of phase and transition signals. Based on a selectable bias level, latched comparators in the latching blocks operate to detect the multi-level input data signal as it crosses a plurality of threshold levels. Logic within the multi-mode phase and data detector selects subsets of exclusive OR gates from sets of exclusive OR gates and subsets of the latching comparators to place the multi-mode phase and data detector in one of a PAM-4, NRZ, or PRML mode of operation. The logic further selects subsets of latched comparators from the plurality of parallel coupled latches to further define the mode of operation of the multi-mode phase and data detector.

NRZ/PAM-4/PRML triple mode phase and data detector

A data density independent clock and data recovery system includes a lock phase adjust charge pump operably coupled to receive phase information and transition information from a phase detector and to produce a current signal, responsive to the phase information and transition information, to a loop filter that converts the current signal to a control voltage signal operably coupled to a voltage controlled oscillator that produces a clock signal to the phase detector based on the control voltage signal. The lock phase adjust charge pump includes a phase charge pump, a transition charge pump, a programmable DC bias current sink, and two programmable offset bias current sinks. The transition charge pump includes a programmable transition current sink. The control logic operates under external control to adjust the currents conducted by the transition charge pump, the programmable DC bias current sink, and the two programmable offset bias current sinks.

Growing community of inventors

Austin, TX, United States of America

Firas Najeh Abughazaleh