Apple Inc.

Tokyo Electron Limited

Dialog Semiconductor Gmbh

Ikanos Communications, Inc.

Semiconductor Components Industries, LLC

Fairchild Semiconductor Corporation

Ming Gu

Mohammad Jafar Navabi-Shirazi

Enzhu Liang

Michail Konstantinos Tsatsanis

Asif Hussain

Jingdong Chen

Behzad Mohtashemi

Kaiwei Yao

Sunil C Shah

Laurent Alloin

Mark Alan Erickson

Ioannis Kanellakopoulos

Laurent Pierrugues

James W Waite

Feng Guo

Cecilia Gabriela Galarza

Yuwen Wang

Daniel Joseph Hernandez

Venkataraman V Iyer

Norman Man Leung Yuen

Omar Alnaggar

Yang Zhang

Thorkell Gudmundsson

Yanhui Xie

Alejandro Lara Ascorra

James E Brown

Thomas E Par&eacute;, Jr

Thomas E Paré, Jr

Jy Ryoo

Di Lin

Fernando Lopez-de-Victoria

Heberly Rosario

A display device include a first light emitting diode (LED), a second LED, and at least one processor of a driver. The processor drives the first LED and the second LED. The processor determines a first pulse width associated with the first LED and a second pulse width associated with the second LED based on a level of brightness to be emitted by the first LED and the second LED. The processor also receives a gap clock and determines a first pulse start time and a first pulse end time for the first LED based on the first pulse width. Moreover, the processor determines a second pulse start time and a second pulse end time for the second LED based on the first pulse end time, the second pulse width, and/or the gap clock, in which the first pulse end time and the second pulse end time are different.

Current load transient mitigation in display backlight driver

Light emitting diode display panels with an open loop amplifier resulting in better brightness accuracy and matching between multiple light emitting diode strings.

Open loop backlight LED driver

Systems and methods for preserving a pulse width modulation (PWM) resolution while increasing the frequency of a pulse width modulation (PWM) clock are provided. An electronic display backlight system may include a backlight element and backlight dimming circuitry. The backlight element may be driven according to a pulse width modulation (PWM) signal over a PWM clock cycle equal to a multiple M of a baseline PWM clock frequency associated with a baseline PWM resolution. The backlight dimming circuitry may receive a brightness code of the baseline PWM resolution and generate the PWM signal at least in part by dividing the brightness code by M.

Systems and methods for increasing a pulse width modulation frequency while preserving resolution

A multi-phase power supply includes a plurality of phase controllers each driving a first terminal of a respective inductor alternatively between an input voltage and a ground voltage to regulate an output voltage in a work mode, keeping the first terminal of the respective inductor in a high impedance state during a non-work mode, having an input for receiving an enable signal for selecting between the work mode and the non-work mode, and generating a current monitor signal to represent a current through the respective inductor during both the work mode and the non-work mode, and a controller coupled to each phase controller for selectively enabling respective ones of the phase controllers in response to a load demand, receiving the current monitor signal from each phase controller, and selectively shutting down the multi-phase power supply when a total of current monitor signals from the phase controller exceeds a threshold.

Inductor current emulation for output current monitoring

A switch mode power supply controller includes a switch terminal adapted to be coupled to an inductor that drives a load, high- and low-side switches a pulse width modulation (PWM) circuit, and a current monitor circuit. The PWM circuit is coupled to a feedback terminal for receiving a feedback signal, and alternatively drives the high-side switch and the low-side switch with a duty cycle set using the feedback signal to regulate an output voltage to a desired level in a work mode, and keeps both the high-side switch and the low-side switch non-conductive in a non-work mode. The current monitor circuit provides a current monitor signal representative of a current driven from the inductor to the load, wherein the current monitor circuit forms the current monitor signal by measuring an inductor current during a work mode, and by emulating the inductor current during a non-work mode.

A display may have an array of pixels illuminated using a backlight unit. The backlight unit may include multiple strings of light-emitting diodes (LEDs) and a boost converter for providing an output voltage to the multiple LED strings. The boost converter may have a single-phase single-switch, single-phase multi-switch, and/or multi-phase multi-switch configuration, where the switches are turned off when the peak current is reached. When transitioning from a single phase to a dual phase operation, the second (slave) phase current may be slowly ramped up. When transition from the dual phase to the single phase operation, the output voltage may be elevated while slowing ramping down the slave phase current. The boost converter may include a current detection circuit for adjusting the peak current of each phase to balance the average current levels. The boost converter may also include an in-rush current controller configured to sense a short fault.

Methods and apparatus for controlling display backlight

The embodiments disclosed herein describe a set of fault detection circuits for LED circuits in an LED channel. A first fault detection circuit is configured to detect a short fault across one or more LEDs. A second fault detection circuit is configured to detect an open fault across an LED. A third fault detection circuit is configured to detect a short across an LED channel transistor. A fourth fault detection circuit is configured to detect an LED channel sense resistor open fault. A fifth fault detection circuit is configured to detect if the LED channel is being intentionally unused. These fault detect circuits can be implemented in a fault detection integrated circuit coupled to the LED channel.

LED driver with comprehensive fault protections

The present invention generally relates to a method and apparatus for effectively detecting and characterizing noise and other events affecting a communications system such as digital subscriber lines (DSL). According to certain aspects, the invention includes a noise analysis engine that is embedded in customer premises equipment that classifies noise sources according to their specific characteristics and tracks each noise source in a dynamic manner, in such a way as to provide visibility to the changing noise environment within the customer premises and/or report this environment to a remote entity.

Method and apparatus for detecting and analyzing noise and other events affecting a communication system

Derivations of new PHY layer diagnostics primitives are based on the normalized error samples collected through G.993.5. The processing uses the ERB and L2 Ethernet packet encapsulation of these ERB data in order to abstract the processing from the PHY layer device dependency, as well as to allow a local and remote processing of the primitives for diagnostics purposes.

Diagnostics primitives on L2/ERB normalized error samples

A method and system for multiline transmission in communications systems are described. Eigenvalues are calculated to maximize equalized channel impulse response (). Eigenvectors associated with dominant eigenvalues are identified (). The eigenvectors are combined into a subspace. Optimization is performed over the subspace to calculate subspace time equalizer coefficients ().

Method and system for providing a time equalizer for multiline transmission in communication systems

A method and apparatus for identification of interference sources are disclosed.

Method and apparatus for characterization of disturbers in communication systems

The present invention includes a method and system for compensating for cross-talk interference in communication systems. The method includes estimation of the interfering signals. Further, the method includes performing a compensation operation on at least one interfering signal.

Method and apparatus for mitigation of disturbers in communication systems

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San Jose, CA, United States of America

Ming Gu