Pmc-sierra, Inc.

Pmc-sierra Us, Inc.

Cadence Design Systems, Inc.

Microsemi Storage Solutions (u.s.), Inc.

Michael Ben Venditti

Julien Faucher

Vadim Milirud

William Michael Lye

Guillaume Fortin

Rania Hassan Abdellatif Abdelrahim Mekky

The present disclosure relates to an apparatus and method for correcting a duty cycle of at least one signal. The apparatus may comprise at least one set of inverters configured to receive the at least one signal and correct the duty cycle of the at least one signal at a correction location of a plurality of correction locations based upon, at least in part, a transmission rate mode of a plurality of transmission rate modes.

Duty cycle correction system and method

The present disclosure provides a means to adjust the relative location of output rising and falling transitions to reduce single-ended duty cycle distortion (DCD) effects in the output data stream originating from the transmitter data path. This serves to improve high-speed single-ended signal characteristics and reduce electromagnetic interference (EMI). Another feature enabled by embodiments of the present disclosure is polarity skew (also referred to as differential skew) reduction between transmitter outputs. In an embodiment, the disclosed method and apparatus for transmitter data path single-ended DCD correction describes a closed-loop calibration system including the actuation apparatus within the transmitter, a sensing block at the output of the transmitter to measure the amount of single-ended DCD, and a calibration block operating on the sensor output to devise correction control inputs to the actuator in the transmitter to correct the data path single-ended DCD present.

Transmitter data path single-ended duty cycle correction for EMI reduction

A circuit and method for improving signal integrity characteristics of a non-full rate transmitter are disclosed herein. The circuit comprises an actuator block having an input for receiving a differential clock signal, the differential clock signal comprising a positive clock signal and a negative clock signal, the actuator configured to adjust a difference between the positive and negative clock signals; a sensing block, for sensing a difference between positive and negative signals of a differential signal, the differential signal being related to the clock signal; and a calibration block for providing a control signal to the actuator based on the sensed difference between the positive and negative signals.

Systems and methods for clock path single-ended DCD and skew correction

Disclosed is a high-swing voltage-mode transmitter or line driver. The transmitter can operate over a wide range of supply voltages. Increasing the available output swing merely involves increasing the supply voltage; the circuit adapts to maintain the desired output impedance. This allows for a tradeoff between output amplitude and power consumption. Another advantage of the proposed architecture is that it compensates for process, voltage, and temperature (PVT) and mismatch variations so as to keep rise and fall times matched. This feature reduces common-mode noise and hence EMI in systems in which the transmitter is used.

Scalable high-swing transmitter with rise and/or fall time mismatch compensation

Apparatus and method for driving a transistor

A method and apparatus to independently adjust the output rise and fall time of a transmitter for the purposes of improving high-speed signaling characteristics and reducing electromagnetic interference (EMI). Also described is an apparatus to provide a high-speed edge-rate control feature. The disclosed method and apparatus for rise and fall time equalization has a closed-loop calibration system that includes an actuation apparatus within the transmitter driver, a sensing means at the output of the transmitter to measure the degree of rise/fall time imbalance, and a calibration state machine operating on the sensor output to devise correction control inputs to the actuator in the transmitter driver to correct the rise/fall time imbalance. Also described is how the actuation apparatus within the transmitter driver can further be used to provide an open-loop edge-rate control feature for the transmitter.

Transmitter output impedance calibration for output rise and fall time equalization and edge rate control

Disclosed is a high-swing voltage-mode transmitter or line driver. The transmitter can operate over a wide range of supply voltages. Increasing the available output swing merely involves increasing the supply voltage; the circuit adapts to maintain the desired output impedance. This allows for a tradeoff between output amplitude and power consumption. Another advantage of the proposed architecture is that it compensates for process, voltage, and temperature (PVT) and mismatch variations so as to keep rise and fall times matched. This feature reduces common-mode noise and hence electromagnetic interference in systems in which the transmitter is used.

Apparatus and method for generating a bias voltage

Configurable voltage mode transmitter architectures are based on combinations of drive cells and parallel termination cells connected in parallel across an external load to provide configurable output characteristics. Each drive cell and parallel termination can be individually enabled, various configurations of enabled cells providing the output characteristics configurability. In some embodiments, dedicated or configured pre-emphasis drive cells with individual enablement capability are added. In some embodiments, pull-down and pull-up cells with individual enablement capability are added to provide additional configurability options. When present, the pre-emphasis, pull-down and pull-up cells are connected in parallel across the external load to provide pre-emphasis features to the output.

Growing community of inventors

Montreal, Canada

Michael Ben Venditti