Sct Technology, Ltd.

O2micro International Limited

O2 Micro, Incorporated

Iml International

Apple Inc.

02 Micro International Limited

Chun Lu

Eric Li

Shang-Kuan Tang

Luyang Luo

Jianping Xu

Shahnad Nadershahi

Dimitry Goder

Alberto Giovanni Viviani

Xinhe Su

Stefan Maireanu

Paolo Sacchetto

Kingsuk Brahma

Jie Won Ryu

Constantin Bucur

Marc Joseph DeVincentis

Mohammad Ali Jangda

Alexandru Hartular

You-Yuh Jack Shyr

ChinFa Kao

JunGi Lee

Lin Tang

Wei Hsin Yao

Yi Zhang

Hyunwoo Nho

Peter F Holland

Yafei Bi

Christopher P Tann

Shengkui Gao

Arthur L Spence

Koorosh Aflatooni

Yang Xu

Vlad Mihail Popescu-Stanesti

Yue Jack Chu

Shean-Yih Chiou

Sinan Alousi

Wenjie Yang

Ardra Singh

Jiwei Chen

Daniel J Drusch

Yutao Chen

Oleg Kobildjanov

Shawn P Hurley

Jongyup Lim

Zhe Hua

Yongqiang Yu

Feng Shi

Alex Hartular

Xiaodong Wang

Kai-Yun Cheng

Jianxin Xue

Shoulin Li

Zhifeng Wen

Xiaohua Lei

Zhitong Lei

Mingzhi He

To reduce overall power consumption for an electronic display power management integrated circuit (PMIC), one of multiple electric power converters and/or electric power regulators may be selected based on an electrical load (e.g., due to the total brightness of the content displayed) on the electronic display at a given moment. In some embodiments, the PMIC may include a less efficient heavy load converter designed with high-current handling capability and a more efficient light load (e.g., low current) converter with lower current handling capability. A controller may dynamically select between the converters depending on a present load or an expected load on the electronic display.

Content-aware dynamic power converter switching for power optimization

Systems, methods, and devices are provided for providing intra-frame luminance scaling to avoid drawing excessive power while still providing exceptional brightness. An instantaneous average pixel luminance of an electronic display may be determined. The instantaneous average pixel luminance may correspond to an amount of light currently being emitted by the electronic display due to a previous image frame and a current image frame. Based at least in part on the instantaneous average pixel luminance, the luminance of a subset of pixels of image data of the current image frame may be adjusted, thereby allowing the electronic display to operate at a relatively high brightness level without exceeding a power limit.

Peak luminance control to enable higher display brightness

A VCOM generator circuit generates a VCOM signal for an electronic display. The VCOM circuit includes an operational amplifier having reduced supply rails. In an implementation, the VCOM circuit has at least three supply rails, AVDD, ground or GND, and VP or VN, or both. VP is less than AVDD and greater than VN. VN is higher than ground and below VP. The VCOM circuit with reduced voltage supply rails for VP and VN reduces power consumption of the VCOM op amps. By reducing power consumption, this also reduces the surface temperature of the integrated circuit.

VCOM with reduced supply rails

An LED lighting device includes multiple luminescent devices driven by a rectified AC voltage. The multiple luminescent devices are turned on flexibly in a multi-stage driving scheme using multiple current controllers. The current settings of the two driving stages with the highest current level and the second highest current level are adjusted according to the variation in the rectified AC voltage Vor according to the variation in the duty cycle of the luminance device due to the variation in the rectified AC voltage. The present invention can improve the line/load regulation of the LED lighting device when the rectified AC voltage somehow fluctuates between its upper bound and lower bound.

Light-emitting diode lighting device having multiple driving stages and line/load regulation control

An LED display system comprises an LED array and an LED driver circuit. An LED driver circuit comprises components including a phase lock loop, a pulse width modulation engine, a configuration register, a series of gain adjustable fast charge current sources, and a serial input/output interface. The components in this driver circuit may be integrated on a same chip. The LED array may be arranged in a common cathode configuration.

LED display systems

The present disclosure provides a circuit for discharging parasitic capacitance in a display panel with common-anode topology having a plurality of light emitters, as well as a circuit for charging parasitic capacitance in a display panel with common-cathode topology. In the common-cathode topology, the circuit includes a three-terminal device having a gate, a source, and a drain, wherein one of the source and the drain is electrically coupled to a common cathode of the light emitters, and a mechanism for controlling the three-terminal device, the mechanism being electrically coupled to the gate. Shortly after a previously selected light emitter is unselected, the mechanism turns on the three-terminal device to form a conductive path between the source and the drain. The mechanism turns off the three-terminal device after a voltage at the common cathode is increased to a predetermined voltage level or after a maximum period of time lapses.

Circuits for eliminating ghosting phenomena in display panel having light emitters

An LED display system comprises an LED array and an LED driver circuit. An LED driver circuit comprises components including a phase lock loop, a pulse width modulation engine, a configuration register, a gain adjustable fast charge current source, and a serial input/output interface. The components in this driver circuit may be integrated on a same chip. The LED array may be arranged in a common cathode configuration.

This disclosure provides a circuit and a method for driving an LED display. The driving circuit comprises a selection circuit for selecting a first light emitter from the plurality of light emitters, a pre-charging circuit for charging an equivalent capacitor of the display panel with respect to the selected first light emitter, and a power circuit for supplying power to the first light emitter after the first light emitter is selected, wherein the power circuit is configured to supply a driving current to the first light emitter in one or more stages. The driving circuit and method of this disclosure can be used to significantly increase the refresh rate and resolution of the LED display.

Circuitry and method for driving LED display

A driving circuit for regulating current in a light source using a tracking component. The tracking component detects the voltage difference between an input node in the input stage and an output node in the output stage. The input stage is connected to a current source and includes an input transistor. The output stage is connected to the light source and includes an output transistor. The tracking component generates an output that controls the input and output transistors based on the voltage difference between the input node and the output node so that the voltage at the input node tracks the voltage at the output node. By using the tracking component, the LED driver can achieve accurate current control through one output transistor instead of cascaded transistors, resulting in lower output operating voltage and reduced power dissipation of the LED driver. Further, the tracking component is intermittently operated or shared across different channels to reduce energy consumption of the LED driver.

Light source driving circuit with low operating output voltage

A current control system includes a first switch, a second switch, and a controller. The second switch is coupled in parallel with the first switch and operable for providing a feedback signal indicative of a current flowing through the first switch. The feedback signal is determined by a width-to-length ratio of the first switch and a width-to-length ratio of the second switch. In addition, the controller is coupled to the first and second switches and operable for adjusting the current according to the feedback signal.

Current control systems with current feedbacks

A system includes a power bus and a circuit. The power bus delivers power from a first power source to an output node. The circuit monitors a current flowing through the power bus and provides power from a second power source to the output node based on an amount of the current, and maintains a voltage level of the output node in a predetermined range.

System for managing power based on current monitoring

A power supply system can include a primary power supply coupled to an output, and a secondary power supply coupled to the output. The primary power supply provides power to the output when a voltage level of the secondary power supply is less than a first predetermined level. The secondary power supply provides power to the output when the voltage level of the secondary power supply is greater than the first predetermined level. The secondary power supply not only provides power to the output, but also charges the primary power supply when the voltage level of the secondary power supply is greater than a second predetermined level that is greater than the first predetermined level.

Power supply topology

A power management system includes a power management unit (PMU) and a current sensor. The PMU is operable for controlling a first power source and a second power source. The second power source is operable for being charged by the first power source via a charging path. The current sensor has a first terminal coupled to the first power source and the second power source and has a second terminal coupled to the second power source via the charging path. The current sensor is operable for sensing a first current flowing from the first power source through the current sensor and for sensing a second current flowing from the second power source through the current sensor.

Power management systems with current sensors

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San Jose, CA, United States of America

Chun Lu