Monolithic Power Systems, Inc.

Realtek Semiconductor Inc.

Industrial Technology Research Institute

Richtek Technology Corporation

Anpec Electronics Corporation

Energy Pass, Inc.

Yu-Huei Lee

Zheng Luo

Junjian Zhao

Ke-Horng Chen

Tong Chen

Chia-Lung Ni

Huan Liu

Shih-Jung Wang

Chao Liu

Tsung-Wei Huang

Shih-Wei Wang

Ying-Hsi Lin

Chih-Heng Su

Chun-Yu Hsieh

Ming-Wei Lin

Yueh-Lung Kuo

Hsuan-Yu Tsai

Ping-Ching Huang

Ze-Qiang Yao

Heng Li

Ying Hsi Lin

Yao-Yi Yang

Suwei Wang

Yi-Ping Su

Liwei Hou

Yu-Ping Huang

Robert Yung-His Tsu

Wei-Chan Wu

Chun-Jen Shih

Ruei-Hong Peng

Yung-Chih Lai

Ching Long Lin

LED driving circuit includes a first current source, a second current source, a current sensing circuit, and a control circuit. The first current source, coupled in series with a heat dissipation resistor, provides a first current path to the LED string. The second current source, coupled in parallel with the serially coupled first current source and the heat dissipation resistor, provides a second current path to the LED string. The current sensing circuit is configured to sense a current sense signal representing a current flowing through the LED string. The control circuit is configured to control a current distribution of the first current path and a second current path in response to the current sense signal. When the current sense signal is greater than a threshold, a current flowing through the first current path is larger than a current flowing through the second current path.

LED driving circuit and method for controlling a current distribution to an LED string

A LED driving system for driving a LED matrix. The LED driving system includes an interconnection structure having a first surface and a second surface opposite to the first surface and a plurality of driver dies/chips attached to the first surface of the interconnection structure. The LED matrix is divided into a plurality of sub LED matrix sections that are attached to the second surface of the interconnection structure. The interconnection structure is configured to electrically couple each one of the plurality of sub LED matrix sections to a corresponding one driver die/chip in the plurality of driver dies/chips.

LED matrix driving system

An LED driving system for synchronizing two LED driving integrated circuits to drive LED strings. The LED driving system sequentially activates the LED strings driven by the first LED driving integrated circuit and then outputs a downstream enabling signal from the first LED driving integrated circuit to the second LED driving integrated circuit to activate the LED strings driven by the second LED driving integrated circuit.

Led driving system with communication between multiple integrated circuits

A feedback control circuit in an LED driving circuit for driving a plurality of LED strings. Each LED string provides a headroom detecting voltage. The feedback control circuit has a status detecting circuit, a counting circuit and a modulating circuit. The status detecting circuit compares each headroom detecting voltage with a low headroom threshold voltage and a high headroom threshold voltage and generates an up self-status signal and a down self-status signal. The counting circuit counts or keeps unchanged and then generates a counting signal based on the up self-status signal and the down self-status signal. The modulating circuit generates a modulating signal based on the counting signal. And based on the modulating signal, the feedback control circuit generates a feedback control signal to regulate a bias voltage supplying the plurality of LED strings.

Adaptive feedback control in LED driving circuits

An LED driving system with a master-slave architecture. The LED driving system has at least two LED driving circuits which both have a first status detecting circuit, a second status detecting circuit and a first feedback control circuit. The first status detecting circuit receives a plurality of headroom detecting voltages provided by a plurality of LED strings and generates at least one self-status signal. The second status detecting circuit receives a downstream feedback signal and generates at least one downstream status signal. The first feedback control circuit generates a first feedback control signal based on the at least one self-status signal and the at least one downstream status signal. The second status detecting circuit of one LED driving circuit is coupled to the first feedback control circuit of the other LED driving circuit.

LED driving system with master-slave architecture

A LED driving system for a LED matrix having a plurality of LEDs connected in parallel. The LED driving system includes a plurality of driving modules. Each one of the plurality of driving modules drives a corresponding one of the plurality of LEDs. The plurality of LEDs are divided into a plurality of groups. The plurality of driving modules drive the plurality of LEDs ON successively group by group. In each one of the plurality of groups, the LESs are driven ON successively row by row, and for each row in each one of the plurality of groups, the LEDs are driven ON successively column by column with a programmed delay time between the LEDs in every two successive columns. Each one of the plurality of driving modules can include a grayscale control module for adjusting a brightness of the corresponding one of the plurality of LEDs.

High brightness LED matrix driving system

A smart communication interface for a LED driving system driving a LED matrix having a plurality of LEDs. The smart communication interface may have a data write transaction structure in write mode. The data write transaction structure includes an address code for identifying a corresponding one LED among the plurality of LEDs; an R/W indicating code for indicating whether the smart communication interface is in write mode; and a grayscale command code for indicating a programmed grayscale command value for the corresponding one LED identified by the address code. The smart communication interface may include a data read transaction structure in read mode. The data read transaction structure includes the address code, the R/W indicating code and a grayscale read-back code for indicating a grayscale command value for the corresponding one LED identified by the address code.

Smart communication interface for LED matrix control

A LED driving system for a LED matrix having a plurality of LEDs connected in parallel. The LED driving system includes a plurality of driving modules. Each one of the plurality of driving modules drives a corresponding one of the plurality of LEDs. Each one of the plurality of driving modules can include a local current driver receiving a reference current and providing a driving current to the corresponding one LED, and a local current tuning module receiving a U-bit current tuning command to tune the driving current for the corresponding one LED to reach a desired driving current using the U-bit current tuning command which provides a predetermined number of tuning steps ranging from 0 to 2U.

Current driving control for high brightness LED matrix

A charger circuit for providing a charging power to a battery includes a power delivery unit and a power conversion circuit. The power conversion circuit includes at least one conversion switch coupled to an inductor, a front stage switch conducting a DC power generated by the power delivery unit to generate a mid-stage power, and a direct charging switch. In a switching charging mode, the conversion switch converts the mid-stage power to the charging current onto a charging node. In a direct charging mode, the power delivery unit regulates the DC current, and the front stage switch and the direct charging switch conduct the DC current onto the charging node. The body diodes of the front stage switch and the direct charging switch are reversely coupled, and the body diodes of the front stage switch and the conversion switch are reversely coupled, for blocking the parasitic body current.

Charger circuit and power conversion circuit thereof

The present invention discloses a current balance circuit for a multiphase DC-DC converter. The current balance circuit comprises a current error calculation circuit, for generating a plurality of current balance signals indicating imbalance levels of a plurality of inductor currents of a plurality of channels of the multiphase DC-DC converter according to a plurality of current sensing signals of the plurality of channels, a time shift circuit, for adjusting pulse widths of a plurality of clock signals according to the plurality of current balance signals, and a ramp generator, for deciding shift levels of a plurality of ramp signals according to the plurality of clock signals.

Current balance circuit and multiphase DC-DC converter and current balance method thereof

A current mode buck-boost converter has an input terminal, an output terminal, and an output capacitor coupled to the output terminal. The input terminal is used to receive an input voltage, and the output terminal is for producing the output voltage. The current mode buck-boost converter comprises a voltage converter and a control circuit. The voltage converter comprises an inductor. The control circuit is for detecting the current passing through the inductor to determine the electric energy transmitted to the output terminal by the voltage converter. Accordingly, the current mode buck-boost converter has fast response, and the electrical energy can be recycled and stored to the voltage source when the current mode buck-boost converter operates in down-tracking process.

Current mode buck-boost converter

The present invention relates to a Single Inductor Double Output (SIDO) power converter, which includes a power-stage circuit, a current detector, a slope compensation device, at least two error amplifiers, a comparing unit, a mode exchange circuit, a logical device and a driver. The SIDO current converter achieves an optimal SIDO power converting efficiency by controlling a full-current mode. Furthermore, different power transferring modes, under a variety of loadings, are used to address the issue of cross regulation and at meanwhile solving output voltage ripples and transient response to ensure the SIDO power converter a more flexible usage environment and better output performance.

SIDO power converter and driving method thereof

A voltage conversion apparatus includes a DC-to-DC conversion circuit, a sensing circuit, and a compensation circuit. The voltage conversion apparatus is capable of adaptively adjusting the system bandwidth according to the load. The system bandwidth is increased to make the converted voltage responding to the load rapidly when the voltage conversion apparatus is operated at a transient state; and the system bandwidth is decreased to increase the system stability when the voltage conversion circuit is operated at a steady state.

Voltage conversion apparatus

A voltage converting circuit including a power stage, a filter, a comparator, a first and a second feedback units. The power stage receives an input voltage and outputs the input voltage according to a duty cycle. The filter receives the input voltage to convert the input voltage into a current, and filters the current to obtain an output voltage. The first feedback unit amplifies a difference between a reference voltage and the output voltage to obtain an error voltage. The second feedback unit calculates the quadratic differential and integration of the output voltage to obtain a sensing voltage. The comparator compares the error voltage and the sensing voltage, and outputs a comparing result to adjust a duty ratio. Herein, a ripple of the output voltage is linearly proportional to that of the current, and DC divided voltage level of the output voltage is substantially equal to the reference voltage.

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Taipei, Taiwan

Yu-Huei Lee