| Patent application number | Description | Published |
|---|
| 20090273285 | PROTECTION FOR EXTERNAL ELECTRODE FLUORESCENT LAMP SYSTEM - The present invention provides a protection means for a driving circuit which drives a set of external electrode fluorescent lamps (EEFL). The driving circuit with protection function for driving a set of EEFLs consistent with the present invention includes: a transformer connected to the set of EEFLs; a switching network connected to the transformer which delivers power to the transformer; a sensing circuit connected to the set of EEFLs which detects disconnection if one light source is disconnected; and a controller connected to the switching network which controls the switching network to reduce the total current supplied to the EEFLs which remain connected, if the sensing circuit detects that one EEFL is disconnected. Appropriate protection can therefore be implemented when the EEFL is disconnected on one end or both ends. | 11-05-2009 |
| 20100033109 | Driving circuit for powering light sources - There is provided a driving circuit for powering a plurality of light sources. The driving circuit includes a power converter, a plurality of switching regulators and a plurality of switching balance controllers. The power converter is operable for receiving an input voltage and for providing a regulated voltage to the light sources. The switching regulators are operable for adjusting forward voltages of the light sources respectively. The switching balance controllers are operable for generating pulse modulation signals to control the switching regulators respectively. | 02-11-2010 |
| 20100039048 | Inverter controller and system - A driving circuit for driving loads includes a switch circuit, a transformer, a current sensing circuit, and an inverter controller. The switch circuit and the transformer are used for converting a DC electric power to an AC electric power so as to energize the loads. The current sensing circuit coupled to the loads generates a feedback current signal indicative of a current flowing through the loads. The inverter controller includes a switch drive circuit, a current regulation circuit receiving the feedback current signal, and a mode controller circuit. The switch drive circuit controls the switch circuit so as to adjust power delivered to the primary winding of the transformer in accordance with the feedback current signal. The mode controller disables the switch circuit through the switch drive circuit if the external signal is in an absence state for a predetermined period. | 02-18-2010 |
| 20100164403 | Circuits and methods for controlling LCD backlights - A circuit for controlling light sources comprises a converter, a feedback circuit and a current distribution controller. The converter is operable for converting an input voltage to an output current and for providing the output current to the light sources. The feedback circuit is coupled to the light sources for generating feedback signals indicative of currents flowing through the light sources respectively. The current distribution controller is coupled to the feedback circuit for generating control signals based on the feedback signals respectively so as to regulate the currents of the light sources respectively, and for controlling the converter to regulate the output current based on the feedback signals. | 07-01-2010 |
| 20100264844 | POWER SYSTEMS WITH PLATFORM-BASED CONTROLLERS - A power system includes a switching circuit, a resonant tank, a feedback circuit, and controller circuitry. The switching circuit including a first switch and a second switch provides a first AC signal. The resonant tank coupled to the switching circuit receives the first AC signal and generating a second AC signal for powering a load. The feedback circuit coupled to the load monitors an electrical condition of the load and provides a feedback signal. The controller circuitry coupled to the converter controls the switching circuit according to the feedback signal so as to control the power to the load. The controller circuitry is integrated in a first die. The first switch is integrated in a second die, and the second switch is integrated in a third die. The first die, said second die and said third die are mounted on and electrically interconnected to a platform compatible with through-hole technology. The platform and the resonant tank are further assembled on a printed circuit board. | 10-21-2010 |
| 20100320934 | CIRCUITS AND METHODS FOR DRIVING A LOAD WITH POWER FACTOR CORRECTION FUNCTION - A circuit for driving a load includes a power line, converter circuitry, and a controller. The power line is operable for providing an input current and an input voltage. The converter circuitry coupled to the power line is operable for converting the input voltage to a regulated voltage to drive the load, and for providing a current detection signal indicating whether a converter current flowing through the converter circuitry drops to a predetermined level. The controller coupled to the converter circuitry is operable for correcting a power factor of the circuit based on the current detection signal and the input voltage such that a waveform of the input current follows a waveform of the input voltage. | 12-23-2010 |
| 20110062869 | CIRCUIT FOR VEHICLE LIGHTING - A circuit for driving a vehicle lamp includes a current path coupled between a power line and ground, and a monitoring unit coupled to the power line. The current path includes a dummy load. The monitoring unit can monitor a testing signal applied to the power line. The testing signal can test whether the vehicle lamp operates properly. The monitoring unit can conduct the current path to enable a current to flow through the dummy load to ground to decrease a total resistance of the circuit if the testing signal is detected. | 03-17-2011 |
| 20110074839 | CONTROLLER CIRCUITRY FOR LIGHT EMITTING DIODES - A method according to one embodiment may include supplying power to an LED array having at least a first string of LEDs and a second string of LEDs coupled in parallel, each of the strings includes at least two LEDs. The method of this embodiment may also include comparing a first feedback signal from the first string of LEDs and a second feedback signal from the second string of LEDs. The first feedback signal is proportional to current in said first string of LEDs and said second feedback signal is proportional to current in said second string of LEDs. The method of this embodiment may also include controlling a voltage drop of at least the first string of LEDs to adjust the current of the first string of LEDs relative to the second string of LEDs, based on, at least in part, the comparing of the first and second feedback signals. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment. | 03-31-2011 |
| 20110109248 | DC/DC CONVERTER WITH MULTIPLE OUTPUTS - Embodiments of the invention provided a DC/DC converter. The DC/DC converter includes a transformer, a first controller and a first switch. The transformer has a primary winding coupled to a power source, a first secondary winding for providing a first output voltage and a second secondary winding for providing a second output voltage. The first controller is coupled to the primary winding for controlling input power to the primary winding to regulate the first output voltage. The switch is coupled to the second secondary winding and for regulating the second output voltage. The first switch is controlled by a pulse modulation signal. A current flows through the second secondary winding if the pulse modulation signal is in the first state, and the current flowing through the second secondary winding remains cut-off if the pulse modulation signal is in the second state. | 05-12-2011 |
