Chunghwa Picture Tubes, Ltd.

Shin-Chang Lin

Bi-Hsien Chen

Han-Yu Chao

Yi-Min Huang

Chien-Yang Chen

Chi-Hsiu Lin

Liang-Che Cho

Chun-Chieh Chiu

Po-Kun Hsieh

Tien Yung Huang

A backlight module driving system and a driving method thereof are applied to a Liquid Crystal Display (LCD). In the LCD, a timing controller obtains a three-dimensional (3D) image signal provided by a graphics processor, generates a Liquid Crystal (LC) driving control signal, and generates a corresponding light adjusting signal according to a data writing time and a Vertical Blanking Interval (VBI) time of the LC driving control signal. A backlight driver obtains and analyzes the light adjusting signal, so as to disable a backlight module during the data writing time, and enable the backlight module during the VBI time.

Backlight module driving system and driving method thereof

A driving circuit includes a signal generator, a resonant circuit, a control circuit and an adjusting circuit. The signal generator is utilized for generating an alternating current (AC) signal having a fixed frequency. The resonant circuit is coupled to the signal generator, and is utilized for generating an oscillation signal to drive a backlight source according to the alternating current signal. The control circuit is utilized for providing a control signal. The adjusting circuit is coupled to the control circuit, the resonant circuit and the backlight source, and is utilized for providing an impedance according to the control signal to thereby adjust a current value of the backlight source.

Driving circuit and method of backlight module

A light source driving circuit includes a power supply circuit, a first dimming circuit, and a control circuit. The power supply circuit has a control terminal and an output terminal that is connected to a terminal of a first light-emitting element. The first dimming circuit has a first terminal connected to the other terminal of the first light-emitting element, a second terminal connected to a common potential, and a pulse width signal input terminal. The control circuit is connected between the pulse width input terminal of the first dimming circuit and the control terminal of the power supply circuit. The first dimming circuit determines an ON/OFF state according to a logic state of the pulse width signal. The power supply circuit determines whether or not to output the voltage. The control circuit delays the power supply circuit, turns off the power supply circuit, and delays the first dimming circuit.

Light source driving circuit

A current-controlling apparatus is suitable for controlling the current passing through a light emitting device string (LEDS), wherein an end of the LEDS is electrically connected to a first-voltage level. The current-controlling apparatus includes a current-adjusting unit and a control unit. The current-adjusting unit, electrically connected between a second-voltage level and another end of the LEDS, is used for detecting a current of the LEDS, producing a feedback signal hereby and controlling the impedance between the LEDS and the second voltage level according to a conductance-controlling signal and an impedance-controlling signal to control the current. The control unit is electrically connected to the current-adjusting unit for receiving a reference signal and the feedback signal, comparing the feedback signal with the reference signal to give a comparison result, performing a current compensation on the comparison result and converting the compensated comparison result into the conductance-controlling signal and the impedance-controlling signal.

Current-controlling apparatus for controlling current of light emitting diode string

A driving circuit, which can realize the driving waveforms for a PDP without staying at ground potential includes having one side, the X side, of an panel equivalent capacitor Cof the PDP coupled directly to ground with the Y side of the equivalent capacitor having a Scan ICconnected to a plurality of switches, each switch coupled to a different voltage source. One of the switches is bi-directional and coupled to ground.

Driving waveform and circuit for plasma display panel

A light source driving circuit includes a voltage signal source and a temperature-improving current source for adjusting luminance of a series of LEDs. A first end of the series of LEDs is electrically connected to a ground end. The temperature-improving current source includes an adjustable power supply for outputting an adjustable voltage, a voltage-controlled current source for outputting currents according to the voltage signal source, and a feedback circuit electrically connected between a second end of the series of the LEDs and the adjustable power supply for controlling the output voltage of the adjustable power supply according to the voltage on the second end of the series of LEDs.

Light source driving module and circuit

A driving circuit for an LED backlight system is disclosed. The driving circuit includes an input voltage, an input resistor, an operational amplifier, a first transistor and a current calculation unit. The operational amplifier has a positive input terminal electrically connected to the input voltage through the input resistor, and an output terminal electrically connected to its negative input terminal thorough a feedback network. The first transistor is utilized for draining a reference current to control an output voltage of the operational amplifier according to the input voltage and the input resistor. The current calculation unit is utilized for generating a plurality of working currents proportional to the reference current to drive a plurality of LED strings according to the output voltage of the operational amplifier.

Driving circuit for LED backlight system

A light source driving circuit for driving a light-emitting element is provided. The light source driving circuit includes a power supply circuit, a dimming circuit, and a feedback circuit/control circuit. The power supply circuit is connected to a terminal of the light-emitting element, and the dimming circuit is connected to the other terminal of the light-emitting element. The feedback circuit/control circuit is connected between the power supply circuit and the dimming circuit. The light source driving circuit uses the feedback circuit/control circuit to delay the dimming circuit to turn off as the light source driving circuit turned off the power supply to stop outputting a voltage to the light-emitted component. Therefore, the light source driving circuit can prevent the breakdown of the dimming circuit caused by over high voltage.

A controlling apparatus for controlling a plurality of LED strings and related light modules is disclosed, wherein each of the plurality of LED strings has a first terminal being electrically connected to an operating voltage. The controlling apparatus includes: a plurality of transistors, each having a control terminal, a first terminal, and a second terminal, wherein the first terminal of each transistor is electrically connected to a second terminal of a corresponding string of the plurality of LED strings, and the second terminals of the plurality of transistors are respectively grounded through a plurality of impedance elements; and a transistor controller, electrically connected to the control terminals of the plurality of transistors, for controlling a current of the first terminal of each transistor by adjusting an input signal of the control terminal of the transistor according to a voltage at the second terminal of the transistor.

Controlling apparatus for controlling a plurality of LED strings and related light modules

A light source driving circuit for driving a light-emitting element is provided. The light source driving circuit includes a power supply circuit, a dimming circuit, and a feedback circuit. A first terminal of the dimming circuit is connected to a terminal of the light-emitting element, and a second terminal of the dimming circuit receives a supply voltage output from the power supply circuit. The dimming circuit determines an ON/OFF state between the first terminal and the second terminal according to a logic state of a pulse width signal. The feedback circuit is connected between the first terminal of the dimming circuit and a feedback terminal of the power supply circuit. The feedback circuit controls a level of the supply voltage output from the power supply circuit according to the ON/OFF state of the dimming circuit.

A claimed multiple mode switch includes an input signal interface for receiving first and second input signals and producing a combined input signal; a driving circuit for receiving the combined input signal and producing driving signals accordingly; a resistor mode circuit electrically connected to a first output of the driving circuit, to a first node, and to a second node for enabling the multiple mode switch to operate in variable resistor mode or in large resistor mode; a fully-on mode circuit electrically connected to the second input signal, the first output of the driving circuit, and the second node for enabling the multiple mode switch to operate in fully-on mode; and a power switch electrically connected to the first node, the second node, and a third node for controlling switching of the multiple mode switch between off mode, fully-on mode, and variable resistor mode or large resistor mode.

Multi-mode switch for plasma display panel

A light source driving circuit is adapted for driving a light-emitted component. The light source driving circuit includes a power supply, a dimming circuit, and a feedback circuit. An output terminal of the power supply is coupled to one terminal of the light-emitted component to supply a power to the light-emitted component, and determine the power value according to a feedback signal received by a feedback terminal of the power supply. A first terminal of the dimming circuit is coupled to another terminal of the light-emitted component. A second terminal of the dimming circuit is coupled to a common voltage. According to a logic state of a pulse width signal, the dimming circuit determines the conduction of the first terminal and the second terminal. The feedback circuit is coupled between the first terminal and the feedback terminal, and determines the feedback signal according to on/off state of the dimming circuit.

Light source driving circuit for driving light emitting diode components and driving method thereof

A plasma display panel driving circuit includes a panel capacitor having first and second sides; a first switch electrically connected between a first voltage and the first side of the panel capacitor; a second switch electrically connected between a second voltage and a first node; a third switch electrically connected between a third voltage and the first side of the panel capacitor; a fourth switch electrically connected between a fourth voltage and the first node; an energy recovery circuit electrically connected between the first side of the panel capacitor and the first node; a fifth switch electrically connected between the first node and a second node; a sixth switch connected between a fifth voltage and the second node; a voltage source connected between the second node and a third node; and a scan IC. The driving circuit can produce driving waveforms that do not need to stay at ground potential.

Driving circuit of plasma display panel

A driver circuit for plasma display panels is provided. The claimed driver circuit includes four switches and an energy recovery circuit coupled to an equivalent capacitor of a plasma display panel. The present energy recovery circuit includes a first unit, coupled to ground and the X side of the equivalent capacitor, for passing current of charging/discharging the equivalent capacitor from the X side and/or Y side; and a second unit, coupled to the first unit and the Y side of the equivalent capacitor, for passing current of charging/discharging the equivalent capacitor from the Y side. With the aid of four voltage sources, it is not necessary for the present energy recovery circuit of the driver circuit to adopt capacitors for charging/discharging the equivalent capacitor of the plasma display panel.

Driver circuit for plasma display panels

A driver circuit for plasma display panels is provided. The claimed driver circuit includes three switches and an energy recovery circuit coupled to an equivalent capacitor of a plasma display panel. The present energy recovery circuit includes a first unit coupled to the X side of an equivalent capacitor and to a first switch, for passing current of charging and/or discharging the equivalent capacitor from the X side; a second unit coupled to the Y side of the equivalent capacitor and to the first switch, for passing current of charging and/or discharging the equivalent capacitor from the Y side; and a third unit coupled to the first switch and ground. The third unit includes a capacitor for charging and/or discharging the equivalent capacitor from the X side and/or the Y side, and a fourth switch coupled to the capacitor in series.

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Taipei Hsien, Taiwan

Shin-Chang Lin