Apparatus and methods for controlling correlated color temperature (CCT) and lighting intensity in lighting fixtures are described. The CCT and intensity may be controlled independently over conventional AC wiring using a conventional dimmer. A lighting controller that resembles a conventional dimmer and that can be installed in place of a dimmer may be used instead of a conventional dimmer to access more control functionalities, still using conventional AC wiring. Wireless communication with the lighting fixture and/or lighting controller are possible.

The invention discloses a method for controlling a bleeder connected to a phase-cut dimmer and a circuit connected to a phase-cut dimmer. The method includes detecting an input voltage of the bleeder to obtain a detection voltage, and comparing the detection voltage and a preset reference voltage, wherein during a first time period, the detection voltage is less than the preset reference voltage, a start point of the first time period is a first moment, and an end point of the first time period is a second moment; delaying a first preset duration on the basis of the second moment to turn off the bleeder; and advancing a second preset duration on the basis of the first moment to turn on the bleeder.

The invention discloses a method for controlling a bleeder connected to a phase-cut dimmer and a circuit connected to a phase-cut dimmer. The method includes detecting an input voltage of the bleeder to obtain a detection voltage, and comparing the detection voltage and a preset reference voltage, wherein during a first time period, the detection voltage is less than the preset reference voltage, a start point of the first time period is a first moment, and an end point of the first time period is a second moment; delaying a first preset duration on the basis of the second moment to turn off the bleeder; and advancing a second preset duration on the basis of the first moment to turn on the bleeder.

A direct, plug-in replacement assembly for the halogen bulb used in existing lighting instruments that are employed in motion picture, video and stage productions. The assembly is self-contained and powered from the same socket as the original bulb. The assembly is designed to fit into the existing lighting instrument without any modification of that instrument. The assembly incorporates an LED array along with an electronic and mechanical system for thermal management. Standard phase-control AC dimmers are fully compatible with the assembly.

A thyristor regulation circuit for a high-voltage light-emitting diode (LED) strip light includes: a live wire input terminal, a neutral wire input terminal, a full-bridge rectifier module, a first group of LED circuit modules, a second group of LED circuit modules, a third group of LED circuit modules, a first thyristor chip, a second thyristor chip and a third thyristor chip. The LED strip light includes a plurality of minimum LED strip light units, the minimum LED strip light units are arranged in parallel, and each of the minimum LED strip light units includes the thyristor regulation circuit for a high-voltage LED strip light. In the thyristor regulation circuit, an external bulky power supply is omitted, and an LED strip light is directly connected to the mains electricity for use, thereby reducing the installation difficulty; and the present disclosure is compatible with existing thyristor dimming circuits.

A LED driving device is provided, which includes a LED string including at least one LED element, at least one channel connected to the at least one LED element, a current regulator configured to regulate a current flowing through the at least one channel according to at least one corresponding control voltage, and a control signal generating circuit configured to generate a control signal based on a difference between a reference voltage and a comparative voltage. The comparative voltage is determined based on a sensing voltage, and the sensing voltage corresponds to an LED current flowing through the LED string. The control signal generating circuit is further configured to generate the at least one corresponding control voltage based on the control signal.

System and method for controlling one or more light emitting diodes. For example, the system for controlling one or more light emitting diodes includes a current regulation circuit coupled to a cathode of one or more light emitting diodes. The one or more light emitting diodes include the cathode and an anode configured to receive a rectified voltage. Additionally, the system includes a control circuit coupled to the cathode of the one or more light emitting diodes. The control circuit is configured to receive a first voltage from the cathode of the one or more light emitting diodes, compare a second voltage and a threshold voltage, and generate a control signal based at least in part on the second voltage and the threshold voltage. The second voltage indicates a magnitude of the first voltage.

System and method for controlling one or more light emitting diodes. For example, the system for controlling one or more light emitting diodes includes a current regulation circuit coupled to a cathode of one or more light emitting diodes. The one or more light emitting diodes include the cathode and an anode configured to receive a rectified voltage. Additionally, the system includes a control circuit coupled to the cathode of the one or more light emitting diodes. The control circuit is configured to receive a first voltage from the cathode of the one or more light emitting diodes, compare a second voltage and a threshold voltage, and generate a control signal based at least in part on the second voltage and the threshold voltage. The second voltage indicates a magnitude of the first voltage.

A two-terminal IC chip and method thereof. For example, a two-terminal IC chip includes a first chip terminal and a second chip terminal. A first terminal voltage is a voltage of the first chip terminal, a second terminal voltage is a voltage of the second chip terminal, and a chip voltage is equal to a difference between the first terminal voltage and the second terminal voltage. The chip is configured to allow a chip current to flow into the chip at the first chip terminal and out of the chip at the second chip terminal, or to flow into the chip at the second chip terminal and out of the chip at the first chip terminal. The chip current is larger than or equal to zero in magnitude. The chip is further configured to change a relationship between the chip voltage and the chip current with respect to time. The chip is an integrated circuit, and the chip does not include any additional chip terminal other than the first chip terminal and the second chip terminal.

A dimming module includes a triggering circuit, a control signal generating circuit, a voltage converting circuit, and a linear driving circuit. The triggering circuit is configured to control a trigger delay angle of an AC input voltage according to a dimming command, in order to output a first voltage signal correspondingly. The control signal generating circuit is configured to output a control voltage according to the first voltage signal. The voltage converting circuit is configured to output a DC operating voltage having an operating level according to the first voltage signal, and output the DC operating voltage to a lighting module, in which the lighting module includes a light-emitting diode. The linear driving circuit is configured to drive the lighting module according to the control voltage.