Patent application number | Description | Published |
20100007287 | MULTI-CHANNEL DRIVING CIRCUIT AND DRIVING METHOD THEREOF - A driving method of a multi-channel driving circuit includes: receiving multiple driving signals corresponding to multiple to-be-driven elements, providing multiple randomized time delays, respectively adjusting the driving signals according to the randomized time delays to generate multiple delayed driving signals, and respectively driving the corresponding to-be-driven elements according to the delayed driving signals. | 01-14-2010 |
20100277214 | DEVICE AND METHOD FOR SIGNAL GENERATION - A signal generator and a method thereof for generating signals are provided. The signal generator includes a pulse width signal generation module and a signal generating module. The pulse width signal generation module generates a first pulse width signal according to a first pulse signal and a second pulse signal. A first signal with a first duty ratio is generated by the signal generating module based on the first pulse width signal. The first duty ratio is equal to a product of a duty ratio of the first pulse signal and a duty ratio of the second pulse signal. | 11-04-2010 |
20110001434 | LED Device and Method for Preventing Soft-Start Flicker - A light-emitting diode (LED) device for preventing soft-start flicker includes an LED module, a voltage converter, a variable current load and a loop control unit. The loop control unit is coupled to the LED module, the voltage converter and the variable current load, and includes a soft-start unit and a dimming control unit. The soft-start unit is utilized for activating a soft-start mechanism of the voltage converter when power of the LED device is turned on. The dimming control unit is utilized for controlling the variable current load to progressively increase a load current of the LED module to a target value and to maintain the load current on the target value until the soft-start mechanism is completed, so as to perform dimming control on the LED module. | 01-06-2011 |
20110018450 | Light Source Driving Device Capable of Dynamically Keeping Constant Current Sink and Related Method - A light source driving device for driving a light emitting component is disclosed. The light source driving device includes a voltage converter coupled to the light emitting component for converting an input voltage into an output driving voltage according to a voltage control signal, a dimming unit coupled to the light emitting component for implementing a dimming process according to a dimming signal, a current source coupled to the dimming unit for providing a driving current to drive the light emitting component, and a control unit coupled to the dimming unit and the voltage converter for detecting a dimming state to generate a dimming detection signal and generating a reference voltage according to the dimming detection signal, wherein the control unit controls the voltage converter to generate the output driving voltage so as to driving the light emitting component. | 01-27-2011 |
20110037396 | LIGHT EMITTING DIODE MODULE AND DRIVING METHOD THEREOF - A light emitting diode module having a plurality of LED strings is provided. The light emitting diode module includes a voltage generating loop, a light tuner, a voltage selector, and a voltage storage and comparison circuit. The voltage generating loop generates a system voltage according to a pulse modulation control signal. The light tuner receives a light tuning signal and turns on or off the LED strings accordingly. The voltage selector selects one of terminal voltages of terminals of the LED strings coupled to the light tuner for generating a selection voltage. The voltage storage and comparison circuit generates an error voltage by comparing the selection voltage and a reference voltage. The voltage storage and comparison circuit stores the error voltage temporarily and provides the temporarily stored error voltage as the pulse modulation control signal. | 02-17-2011 |
20110037410 | Control Method Capable of Preventing Flicker Effect and Light Emitting Device Therefore - A control method capable of preventing flicker effect for a light source module includes detecting variation situations of a driving current passing through the light source module to generate a current detection signal, adjusting a variable reference voltage according to the current detection signal, obtaining a feedback voltage from the light source module, generating a voltage control signal according to the feedback voltage and the variable reference voltage, and generating an output voltage according to the voltage control signal to drive the light source module. | 02-17-2011 |
20110043114 | LED Device with Simultaneous Open and Short Detection Function and Method Thereof - An LED device with simultaneous open and short detection function includes a plurality of LED strings, a voltage converter, a current driving unit, a loop control unit, an open detector, a short detector and a voltage detector. The open detector and the short detector are utilized for detecting LED open and LED short for the plurality of LED strings, respectively. The voltage detector is coupled to the open detector, the short detector and the voltage converter, and is utilized for generating a reset signal to the short detector according to an output voltage of the voltage converter when the LED open occurs on the plurality of LED strings, so as to initiate the LED short detection for the plurality of LED strings again. | 02-24-2011 |
20110043138 | Light Emitting Device Capable of Dynamically Regulating Output Voltage and Related Control Method - A light-emitting diode (LED) device capable of dynamically regulating output voltage is disclosed. The LED device includes a plurality of LED chains, a voltage converter, a current driving unit, a loop control unit. The loop control unit is coupled to the LED chains and the voltage converter, and includes a voltage selection unit, an error amplifier, and a conversion controller. The voltage selection unit is utilized for generating a plurality of candidate voltages according to a threshold voltage and a plurality of headroom voltage voltages corresponding to the LED chains and the current driving unit, and selecting a feedback voltage from the candidate voltages. The error amplifier generates an error voltage signal according to a reference voltage and the feedback voltage. The conversion controller generates a voltage control signal according to the error voltage signal to control the voltage conversion of the voltage converter. | 02-24-2011 |
20110062887 | DRIVING APPARATUS OF LIGHT EMITTING DIODE AND DRIVING METHOD THEREOF - A driving apparatus of a light emitting diode (LED) and a driving method thereof are provided. In the driving method, when the driving apparatus performs dimming and a duty cycle of a dimming signal is smaller than a predetermination value, outputting time of driving currents are equally allotted in a period, and a magnitude of each driving current is regulated correspondingly. When the driving apparatus performs dimming and the duty cycle of the dimming signal is equal to or greater than the predetermination value, the driving currents are simultaneously output in the period, and the magnitude of each driving current is regulated according to the dimming signal. Therefore, an audio noise and an electromagnetic interference caused by excessive variation of a sum of the driving currents are suppressed. | 03-17-2011 |
20110074468 | FREQUENCY GENERATOR - A frequency generator is used for generating a frequency within a frequency range. The frequency generator includes a variable current source, a voltage drop generation unit, a voltage source, a detection unit, a conversion unit, and an oscillating circuit. The variable current source is used for outputting a current according to a control signal. The voltage drop generation unit is used for generating a voltage drop according to the current. The voltage source is used for outputting a voltage range. The detection unit is used for outputting the control signal to the variable current source according to a relationship between the voltage drop and the voltage range. The conversion unit is used for outputting a digital code according to the relationship between the voltage drop and the voltage range. The oscillator circuit is used for generating the frequency according to the digital code. | 03-31-2011 |
20120139434 | DRIVING APPARATUS OF LIGHT EMITTING DIODE AND DRIVING METHOD THEREOF - A driving method of a light-emitting diode (LED) adapted to a driving apparatus is provided. The driving method includes receiving a dimming signal, detecting whether the driving apparatus performs dimming, and if the driving apparatus performs dimming, determining whether a duty cycle of the dimming signal is smaller than a predetermined value. When the duty cycle of the dimming signal is not smaller than the predetermined value, respective current magnitudes of a plurality of driving currents are regulated according to the dimming signal, and each of the driving currents is output for a full time of a period. Conversely, when the duty cycle of the dimming signal is smaller than the predetermined value, each of the driving currents is output for a partial time of a period. A driving apparatus employing the driving method is also provided. | 06-07-2012 |
20120286677 | DRIVING APPARATUS OF LIGHT EMITTING DIODE AND DRIVING METHOD THEREOF - A driving method of a light-emitting diode (LED) adapted to a driving apparatus is provided. The driving method includes detecting whether the driving apparatus performs dimming, and if the driving apparatus performs dimming, determining whether a predetermined requirement for dimming control is met or not. When the predetermined requirement for dimming control is not met, respective current magnitudes of a plurality of driving currents are regulated, and each of the driving currents is output for a full time of a period. Conversely, when the predetermined requirement for dimming control is met, each of the driving currents is output for a partial time of a period. | 11-15-2012 |
20130082603 | LED Device with Simultaneous Open and Short Detection Function and Method Thereof - An LED device with simultaneous open and short detection function includes a plurality of LED strings, a voltage converter, a current driving unit, a loop control unit and an open and short detector. The open and short detector is utilized for performing LED open and LED short detection on the plurality of LED strings according to negative electrode voltages of the plurality of LED strings and a level variation trend of a second voltage converted from a first voltage by the voltage converter. | 04-04-2013 |