A light emitting diode (LED) driving circuit including a dimmer modulating an AC voltage input depending on a selected dimming level, a rectifying unit performing a full-wave rectification for an AC voltage to generate and output a driving voltage, first and second dimming level detecting units receiving the driving voltage of the rectifying unit to detect the selected dimming level, and outputting first and second dimming level signals depending on the detected dimming level, a first driving module controlling a first LED light emitting unit using the first dimming level signal of the first dimming level detecting unit, and a second driving module controlling a second LED light emitting unit using the second dimming level signal of the second dimming level detecting unit, in which the first and second driving modules control the first and second LED light emitting units, respectively.

A lighting application is provided that includes an LED assembly including a serial connection of two or more LED units, each LED unit including one or more LEDs, each LED unit being provided with a controllable switch for substantially short-circuiting the LED unit. The lighting application further includes a control unit for controlling a drive unit and arranged to receive a signal representing a voltage level of the supply voltage, and control the switches in accordance with the signal. An LED driver is provided that enables to operate a TRIAC based dimmer at an optimal holding current and an LED driver including a capacitor as a switchable buffer.

The present invention relates to a driver device (60) for driving a load (12), in particular an LED unit comprising one or more LEDs, said driver device comprising input terminals (28, 30) for receiving an input voltage (V12) from an external power supply (16), output terminals for providing an output voltage to the load (12) for driving the load (12), a converter unit (34) for converting the input voltage (VI 2) to a converted voltage (VI 4) and for providing the converted voltage (VI 4) to internal connection elements (63, 64) of the driver device (60), a signal control device (62) for applying an electrical signal (I) to at least one of the connection elements (63, 64), and a detection circuit for detecting a phase angle of the input voltage (VI 2) by measuring a voltage drop of the converted voltage (VI 4) caused by the electrical signal (I).

The invention relates to a device for operating LEDs, comprising a driver module and an LED module (11), which is controlled by the driver module (10) and has at least one LED. The LED module (11) is fed a current by the driver module (10) via a first connection (1), and a second connection (2) is present, preferably as a ground connection (GND). The device is characterized in that the LED module (11) is connected to the driver module (10) by means of a third connection (3), which is designed as a data channel, a voltage fed by the driver module (10) being applied to the data channel.

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 generator configured to generate a first current flowing through one or more light emitting diodes. The one or more light emitting diodes are configured to receive a rectified voltage generated by a rectifying bridge coupled to a TRIAC dimmer. Additionally, the system includes a bleeder configured to receive the rectified voltage, and a controller configured to receive a sensing voltage from the current generator and output a control signal to the bleeder. The sensing voltage indicates a magnitude of the first current.

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 generator configured to generate a first current flowing through one or more light emitting diodes. The one or more light emitting diodes are configured to receive a rectified voltage generated by a rectifying bridge coupled to a TRIAC dimmer. Additionally, the system includes a bleeder configured to receive the rectified voltage, and a controller configured to receive a sensing voltage from the current generator and output a control signal to the bleeder. The sensing voltage indicates a magnitude of the first current.

Disclosed are an LED control circuit and device compatible with a silicon-controlled dimmer, and a control method. The LED control circuit comprises a silicon-controlled dimmer, a rectifier module, a bleeder module, a control module, a voltage detection module, and a constant-current source module. An alternating current is input to the silicon-controlled dimmer and the rectifier module and then a line voltage is output to the voltage detection module; the voltage detection module outputs a voltage detection signal to the control module according to the change of the line voltage and outputs a phase angle detection signal to the constant-current source module; the control module controls on or off of the bleeder module according to the voltage detection signal, and a bleeder current when the bleeder module is turned on is greater than a maximum charging current before the silicon-controlled dimmer is conducted.

Disclosed are an LED control circuit and device compatible with a silicon-controlled dimmer, and a control method. The LED control circuit comprises a silicon-controlled dimmer, a rectifier module, a bleeder module, a control module, a voltage detection module, and a constant-current source module. An alternating current is input to the silicon-controlled dimmer and the rectifier module and then a line voltage is output to the voltage detection module; the voltage detection module outputs a voltage detection signal to the control module according to the change of the line voltage and outputs a phase angle detection signal to the constant-current source module; the control module controls on or off of the bleeder module according to the voltage detection signal, and a bleeder current when the bleeder module is turned on is greater than a maximum charging current before the silicon-controlled dimmer is conducted.

System and method for controlling one or more light emitting diodes. For example, the system includes: a phase detector configured to process information associated with a rectified voltage generated by a rectifier and related to a TRIAC dimmer, the rectified voltage corresponding to a first waveform during a first half cycle of an AC voltage and corresponding to a second waveform during a second half cycle of the AC voltage, the phase detector being further configured to generate a phase detection signal representing a first time duration during which the first waveform indicates that the rectified voltage is larger than a predetermined threshold and representing a second time duration during which the second waveform indicates that the rectified voltage is larger than the predetermined threshold; and a mode detector configured to process information associated with the rectified voltage.

The present application provides a control circuit and a control method with fixed bleed time, a trigger signal is obtained and transmitted via a detection module; a timing module starts timing upon receiving the trigger signal, and outputs an end-of-timing signal when a preset time is reached; a control module outputs a control signal according to the end-of-timing signal; a bleeder module bleeds off a current within the preset time according to the control signal; and when the control circuit is powered off, the detection module, timing module, control module and bleeder module automatically perform a power-off reset.