Lx Semicon Co., Ltd.

Sang Suk Kim

Jang Su Kim

Jong Min Lee

Ji Hwan Kim

Kyeong Rok Lee

Yun Sung Wang

Soon Hyeok Kwak

The present embodiment relates to a technology for facilitating an increase of the number of LEDs to be driven by communication of a clock signal between chips forming a daisy chain when driving LEDs. The communication of a clock signal as well as data between chips allows improve the synchronization between the clock signal and data.

LED driving circuit and driving method thereof

An LED driving circuit adjusts a PWM driving frequency in light emitting diode driving, and changes a PWM frequency of an LED driving circuit in response to a frequency of a PWM clock signal delivered externally or internally.

LED driving circuit and its driving method

The present disclosure relates to an LED driving circuit for controlling the voltage of an LED backlight system, and to a technology for controlling the driving voltage of an LED string formed at one end of the LED string through a digital counter by monitoring the output voltage of the LED string.

LED driving circuit and driving method

A hybrid dimming control device, which prevents image quality degradation during local dimming of a backlight unit, includes an analysis circuit configured to determine a type of dimming data for controlling the local dimming of a light source included in a backlight unit by analyzing the dimming data, a pulse width modulation (PWM) dimming control circuit configured to control the local dimming of the light source by a PWM method when the type of the dimming data is a first type, and an active dimming control circuit configured to convert some bits of the dimming data into an analog signal and control the local dimming of the light source using the analog signal when the type of the dimming data is a second type.

Hybrid dimming control device and hybrid dimming control method

The present disclosure relates to a technology for performing a hybrid driving in order to increase accuracy of a low current driving when driving a light emitting diode and allows an LED driving circuit to perform a PWM driving when a current is low and to perform a PAM driving when a current is high and this leads to an elaborate adjustment of a grayscale.

A current mirror circuit includes a first transistor configured to be supplied with a data current from a data driving circuit; a second transistor configured to drive a light emitting diode by mirroring the data current transferred to the first transistor; and a voltage compensation circuit disposed between one terminal of the first transistor and one terminal of the second transistor and configured to compensate for a difference between voltages of the one terminals of the first transistor and the second transistor.

Current supply circuit and display device including the same

A system for controlling backlight unit capable of reducing a time difference between an image displayed on a display panel and local dimming of the backlight unit, includes a plurality of dimming control devices configured to receive an input data packet including dimming data, and control local dimming of a light source, which is included in a region assigned in advance in a backlight unit, using the dimming data, a plurality of gate lines configured to electrically connect a predetermined number of dimming control devices and configured to be sequentially driven according to a row driving method, and a micro controller unit configured to generate a gate control signal for driving the plurality of gate lines and the input data packet.

System and method for controlling back light unit

The present embodiment relates to a communication protocol between an MCU and an LED driving circuit for LED driving. The MCU may define and use an SPI protocol including ID setting, a command, configuration data, etc.

The present disclosure provides a current mirror circuit including a first transistor configured to be supplied with a data current from a data driving circuit; a second transistor configured to drive a light emitting diode by mirroring the data current transferred to the first transistor; a capacitor disposed between the first transistor and the second transistor and configured to store a voltage of a gate terminal of the second transistor therein; and a first switch disposed between the first transistor and the second transistor and configured to adjust an input current of the gate terminal of the second transistor.

A current supply circuit according to the present disclosure may include a voltage/current converter configured to convert, into a data current, a data voltage received from a data driving circuit and a first current mirror circuit configured to mirror the data current so that a light-emitting diode (LED) current flows into an LED array. The data current may be adjusted based on a greyscale value of the LED array.

Growing community of inventors

Daejeon, South Korea

Sang Suk Kim