Himax Technologies, Inc.

Shu-Ming Chang

Shwang-Shi Bai

Shen-Yao Liang

Yu-Pei Huang

Hsiu-Na Hsieh

Hung-Yu Huang

Tsung-Yi Tsai

Sheng-Wen Huang

I-Sheng Lin

Shiang-Wei Wang

Chia-Hui Wang

A method of performing power saving control on a display device includes: generating, by a timing controller of the display device, a power saving start indication and a power saving end indication in response to changing of a refresh rate of the display device; receiving, by a source driver of the display device, the power saving start indication and the power saving end indication; in response to the power saving start indication, allowing a part of circuitry of the source driver to be powered down during a vertical blanking interval; and in response to the power saving end indication, allowing the powered down part of circuitry of the source driver to be woken up during the vertical blanking interval.

Method of performing power saving control on display device and related display device

An LCD (liquid crystal display) power supply includes an AC to DC converter circuit, a transformer, a DC to AC converter, and a feedback circuit. The AC to DC converter circuit couples an AC power supply to generate a DC signal. The DC to AC converter couples the DC signal to a primary side of the transformer and alternates polarities thereof so that an AC signal is generated on a secondary side of the transformer to supply for a load. The feedback circuit receives a first feedback signal indicative of power being supplied to the load and modulates the DC signal generated by the AC to DC converter circuit according to the first feedback signal.

LCD power supply

An inverter circuit for driving a lamp and a backlight module using the same are provided. The inverter circuit includes a signal generation module, a switching unit, a first capacitor, a transformer and a first detecting module. The signal generation module generates a pulse width modulation (PWM) signal, wherein the duty cycle of the PWM signal is controlled by a feedback signal and a sensed signal. The switching unit has a control terminal receiving the PWM signal, and has a first current terminal and a second current terminal respectively coupled to a first terminal and a second terminal of the first capacitor. The transformer generates an AC driving signal to the lamp according to a signal variation of the primary winding coupled the first current terminal of the first transistor. The first detecting module generates the sensed signal according to the flowing current of the switching unit.

Inverter circuit of driving a lamp and backlight module using the same

The invention is a driving apparatus and circuit for efficiently converting a direct current (DC) signal into an alternating current (AC) signal to drive a fluorescent lamp. A semi class E configuration which utilizes only one transistor is employed in the invention. The invention comprises a power transistor, a transformer wherein a primary winding is used as a load for the power transistor and a secondary winding is used to transfer energy to the load for the driving apparatus, i.e. the CCFL tube, and control means which extracts the frequency and current of the power transistor and corrects the deviation between the frequency of the power transistor and that of the control means.

High efficiency and low cost cold cathode fluorescent lamp driving apparatus for LCD backlight

A backlight module and a current providing circuit thereof are provided. The current providing circuit includes a signal generating unit, a switching unit, a first capacitor, a transformer and an output node. The signal generating unit generates a PWM signal according to a level of a power source. The switching unit determines whether a first signal end and a second signal end of the switching unit are conducted according to the PWM signal received by a control end of the switching unit. Following a switch performed by the switching unit, the first capacitor charges and discharges through a current path provided by a primary coil of the transformer. Thereby, a secondary coil of the transformer generates a corresponding AC voltage by sensing a current change in the primary coil and outputs the AC voltage through the output node.

Backlight module and current providing circuit thereof

A driving system, includes: a power supply unit for providing a first current and a second current; a first transformer having a primary side coupled to the power supply unit and a secondary side coupled to a first current balancing circuit for driving a plurality of first lamps; a second transformer having a primary side coupled to the power supply unit and a secondary side coupled to a second current balancing circuit for driving a plurality of second lamps; a balancing control circuit coupled to the power supply unit for balancing the first and the second current so that the first current and the second current are substantially equal.

Driving system for electronic device and current balancing circuit thereof

A DC-AC converter includes a signal generating module, a first switch, a first capacitor, a transformer, and a trigger signal generating module. The signal generating module generates a pulse width modulation (PWM) signal according to a trigger signal. The first switch has a control terminal receiving the PWM signal, and a first terminal and a second terminal coupled to a first terminal and a second terminal of the first capacitor respectively. The transformer has a primary winding coupled to the second terminal of the first switch, and a secondary winding coupled to a load. The transformer generates a driving signal to the load according to a signal variation of the primary winding. The trigger signal generating module compares a first signal outputted from the second terminal of the first switch with a phase delay signal thereof and thereby generates the trigger signal for controlling the frequency of the PWM signal.

DC-AC converter

An inverter has an inductor, a capacitor, a switching device, a driving circuit and a transformer. A first terminal of the capacitor is connected to the inductor, and the switching device is connected between the first terminal of the capacitor and a ground terminal. The driving circuit is connected to the switching device, wherein the driving circuit is arranged to control the switching device to turn on or turn off; and a primary side of the transformer is connected between a second terminal of the capacitor and the ground terminal.

Inverter having single switching device

A lamp driving device has a pulse width modulation circuit, a phase splitter and several switching circuits. The pulse width modulation circuit is arranged to generate a pulse width modulation signal. The phase splitter is coupled to the pulse width modulation circuit and arranged to split the pulse width modulation signal into several phased signals having different phases, wherein pulses of each phased signal are non-overlapping with those of another phased signal. The switching circuits are coupled to the phase splitter and are arranged to respectively receive one of the phased signals, wherein each switching circuit is controlled by the received phased signal.

Lamp driving device and method

A backlight driver circuit has a transformer, a switching circuit and a plurality of switch devices. The switching circuit couples a DC voltage to a primary side of the transformer and alternates polarities thereof so that an AC voltage is generated on a secondary side of the transformer to turn on the backlight blocks. The switch devices are respectively connected between one of the backlight blocks and the transformer, and the AC voltage turns the backlight blocks on when the switch devices are turned on.

Growing community of inventors

Tainan County, Taiwan

Shu-Ming Chang