International Business Machines Corporation

Kabushiki Kaisha Toshiba

Toshiba America Electronic Components, Inc.

Sony Computer Entertainment Inc.

Toshiba America Electronics Components, Inc.

Toshiba American Electronic Components, Inc.

David William Boerstler

Eskinder Hailu

Jieming Qi

Kazuhiko Miki

Hung Cai Ngo

Masaaki Kaneko

Kevin John Nowka

Gary Dale Carpenter

Mack Wayne Riley

Daniel Mark Dreps

Harm Peter Hofstee

Eric John Lukes

Bin Wan

James David Strom

Michael Fan Wang

Byron Lee Krauter

Hiroki Kihara

Edward B Eichelberger

Charles B Winn

Gary T Hendrickson

Mike Shen

Kirk David Peterson

Robert K Montoye

Mark Edward Dean

John Samuel Liberty

Stephen Douglas Weitzel

Juan-Antonio Carballo

Munehiro Yoshida

Andrew Christian Zimmerman

Sang Hoo Dhong

Anthony Gus Aipperspach

Nathaniel R Chadwick

Jeffrey L Burns

Matthew E Fernsler

Franklin M Baez

Hayden C Cranford, Jr

Subramanian Srikanteswara Iyer

Joel Abraham Silberman

Peter Juergen Klim

Sani Richard Nassif

Dieter F Wendel

Christopher McCall Durham

Osamu Takahashi

Peichun Peter Liu

Yosuke Muraki

John Beck

Makoto Aikawa

Robert Walter Berry, Jr

Steven Mark Clements

Norman Karl James

Minhan Chen

Daniel J Stigliani, Jr

Gilles Gervais

Iwao Takiguchi

Tetsuji Tamura

Ivan Vo

H Peter Hofstee

Li Shi

Chulwoo Kim

Juan Antonio Carballo

Toshiyuki Ogata

Bert W Weidle

A method and apparatus for translating signals between different components located in different power boundaries in a mixed voltage system. A level shifter system includes a first level shifter circuit connected to a first voltage source. A second level shifter circuit connects to a second voltage source. An intermediate level shifter circuit has an input that connects to the output of the first level shifter circuit. The output of the intermediate level shifter circuit connects to the input of the second level shifter circuit. The intermediate level shifter circuit uses an intermediate voltage source having an intermediate voltage about midway between the first voltage of the first voltage source and the second voltage of the second voltage source.

Self-biased high speed level shifter circuit

A design structure for a Duty Cycle Correction (DCC) circuit is provide in which pairs of field effect transistors (FETs) in known DCC circuit topologies are replaced with linear resistors coupled to switches of the DCC circuit such that when the switch is open, the input signal is routed through the linear resistors. The linear resistors are more tolerant of process, voltage and temperature (PVT) fluctuations than FETs and thus, the resulting DCC circuit provides a relatively smaller change in DCC correction range with PVT fluctuations than the known DCC circuit topology that employs FETs. The linear resistors may be provided in parallel with the switches and in series with a pair of FETs having relatively large resistance values. The linear resistors provide resistance that pulls-up or pulls-down the pulse width of the input signal so as to provide correction to the duty cycle of the input signal.

Structure for a duty cycle correction circuit

A design structure of a circuit for managing voltage swings across FETs comprising a reference precision resistor, a first and second FET, wherein a gate of the first FET is tied to a gate of the second FET, wherein a drain to source resistance of the second FET is substantially equal to or is a multiple of a resistance of the reference precision resistor, and wherein a gate voltage of the second FET is applied to a gate of the first FET to set a bias point of the first FET, and a third FET cascoded to the first FET, wherein a source of the first FET is coupled to the drain of the third FET to extend a voltage range in which respective gate voltages of the first and third FETs maintain a linear relationship with respective drain to source voltages of the first and third FETs.

Structure for managing voltage swings across field effect transistors

A variable gain amplifier includes a first common mode (CM) node configured to receive a first differential signal of a pair of differential signals. A first regulator couples to the first CM node, the first regulator being configured to generate a first CM offset. A second CM node is configured to receive a second differential signal of the pair of differential signals. A second regulator couples to the second CM node, the second regulator being configured to generate a second CM offset. In one embodiment, the first CM offset and the second CM offset together comprise a net CM offset, the net CM offset being configured to replace a current source net offset.

Variable gain amplifier with reduced power consumption

A design structure for a circuit for obtaining a desired phase locked loop (PLL) duty cycle without a pre-scaler is provided. The PLL circuit of the illustrative embodiments utilizes two separate loops that simultaneously operate on the VCO. One loop ensures the frequency and phase lock while the other loop ensures the duty cycle lock. The VCO is modified to have an additional control port to adjust the duty cycle. Thus, the VCO has one control port for performing frequency adjustment and one control port for duty cycle adjustment. As a result, both the duty cycle and the frequency may be controlled using the VCO of the PLL circuit of the illustrative embodiments so as to achieve any desired duty cycle output without requiring a VCO pre-scaler circuit or duty cycle correction circuit.

Structure for a circuit obtaining desired phase locked loop duty cycle without pre-scaler

The present invention provides for a method for characterization of pulse-width limiter outputs. A known clock signal is received. A pulse width of the received known clock signal is limited through a first pulse-width limiter to generate a first intermediate signal. The first intermediate signal is delayed by a known amount to generate a first delayed signal. The first intermediate signal is inverted to generate a first inverted signal. A pulse width of the first inverted signal is limited through a second pulse-width limiter to generate a second intermediate signal. The second intermediate signal is delayed by a known amount to generate a second delayed signal. A logic OR operation is performed on the first delayed signal and the second delayed signal to generate a clock out signal.

System and method for on/off-chip characterization of pulse-width limiter outputs

Embodiments of the disclosure provide systems and methods for clock duty cycle measurement. A clock signal and a complement of the clock signal are provided to a charge pump during first and second predetermined timing windows. A charge pump is operable to generate first and second output voltages in response to the clock signal and the complement of the clock signal during the first and second timing windows, respectively. In addition a predetermined positive voltage and a ground voltage are applied to the charge pump during predetermined third and fourth timing windows, respectively. The charge pump is operable to generate third and fourth output voltage signals corresponding to the predetermined positive and ground voltages during the third and fourth timing windows, respectively. The first, second, third and fourth voltages are then used to calculate the duty cycle of the clock.

Clock duty cycle measurement with charge pump without using reference clock calibration

A design structure embodied in a machine readable medium used in a design process includes an interleaved voltage-controlled oscillator, including a ring circuit of main logic inverter gates; a plurality of delay elements connected in parallel with a selected sequence of the main logic inverter gates; wherein each delay element comprises a feedforward section, comprising controls for regulating signal transmission through feedforward elements responsive to one or more control voltages; and a proportional section for regulating signal transmission through at least one logic inverter gate; at least one temperature compensation circuit responsive to a compensating voltage input that is proportional to temperature; an electronic circuit in communication with the temperature compensation circuit and configured to provide a voltage signal responsive to temperature; an amplifier in connection with the electronic circuit to amplify the voltage signal; and a DC offset generator configured to adjust the voltage of the amplified voltage signal.

Structure for interleaved voltage controlled oscillator

A design structure for a circuit for measuring the absolute duty cycle of a signal, is provided. A non-inverted path from a signal source is selected and various DCC circuit setting indices are cycled through until a divider, coupled to the output of the DCC circuit, fails. A first minimum pulse width at which the divider fails is then determined based on the index value of the DCC circuit at the time of the failure. An inverted path from the signal source is selected and the various DCC circuit setting indices are cycled through again until the divider fails. A second minimum pulse width at which the divider fails is then determined based on the index value of the DCC circuit at the time of this second failure. The duty cycle is then calculated based on a difference of the first and second minimum pulse width values.

Structure for an absolute duty cycle measurement circuit

Systems and methods for enabling the determination of voltage controlled oscillator (VCO) linearity, duty cycle determination and duty cycle correction in phase locked loop circuits (PLL's.) One embodiment comprises a method including the steps of determining the frequency response of a PLL's VCO as a function of duty cycle, applying a signal based on the VCO output to the VCO input, measuring the resulting frequency of the VCO output signal, determining the duty cycle corresponding to the measured frequency, and configuring a duty cycle correction unit correct the duty cycle of the VCO output signal to about 50%. Determining the frequency response of the VCO may include, for each of several different duty cycle values between 0% and 100%, applying the VCO input signal to the VCO and determining the corresponding frequency of the VCO output signal. This may also be done for duty cycles of 0% and 100%.

Systems and methods for PLL linearity measurement, PLL output duty cycle measurement and duty cycle correction

A design structure for a programmable interpolative voltage controlled oscillator (VCO) with adjustable frequency range output is provided. Programmable delay cells whose size is modifiable based on control inputs to the programmable delay cells are utilized. A different set of control inputs may be provided to programmable delay cells of an inner sub-ring from the set of control inputs provided to programmable delay cells of a main ring of the VCO. The minimum frequency output of the VCO is governed by the main ring programmable delay cell strength with the maximum frequency output of the VCO being governed by a ratio of strengths of the main ring programmable delay cells to the inner sub-ring programmable delay cell. By modifying the control inputs to the inner sub-ring and main ring programmable delay cells, the minimum and maximum frequency outputs, and thus the range between these two frequency outputs, are made programmable.

Structure for a programmable interpolative voltage controlled oscillator with adjustable range

A design structure for a hybrid phase locked loop (PLL) circuit that obtains stabilized dynamic response and independent adjustment of damping factor and loop bandwidth is provided. The hybrid PLL circuit of the illustrative embodiments includes the resistance/capacitance (RC) filter elements of a conventional RC PLL and the feed-forward path from the output of the phase frequency detector to the voltage controlled oscillator (VCO). The hybrid PLL essentially enhances the performance of the conventional feed-forward PLL by providing the RC filter whose components can be weighted to provide a dynamic response that is significantly less sensitive to parameter variation and which allows loop bandwidth optimization without sacrificing damping.

Design structure for a phase locked loop with stabilized dynamic response

A method, an apparatus, and a computer program are provided to measure and/or correct duty cycles. Duty cycles of various signals, specifically clocking signals, are important. However, measurement of very high frequency signals, off-chip, and in a laboratory environment can be very difficult and present numerous problems. To combat problems associated with making off-chip measurements and adjustments of signal duty cycles, comparisons are made between input signals and divided input signals that allow for easy measurement and adjustment of on-chip signals, including clocking signals.

Digital circuit to measure and/or correct duty cycles

A design structure for a circuit for measuring the absolute duty cycle of a signal anywhere on an integrated circuit device is provided. The circuit has a plurality of substantially identical pulse shaper elements, each of which expand the pulse of an input signal whose duty cycle is to be measured by a same amount. The outputs of the pulse shaper elements may be coupled to substantially identical divider circuits whose outputs are coupled to a multiplexer that selects two inputs for output to a set of master/slave configured flip-flops, one input serving as a clock and the other as data to the flip-flops. The flip-flops sample the divider outputs selected by the multiplexer to detect if the dividers have failed or not. The outputs of the flip-flops are provided to an XOR gate which outputs a duty cycle signal indicative of the duty cycle of the input signal.

Structure for a duty cycle measurement circuit

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Round Rock, TX, United States of America

David William Boerstler