A dummy load for automotive LED lights is revealed. The dummy load includes an automotive battery and a control module which is electrically connected both a body computer and a LED light module and provided with a LED control circuit and a charge control circuit. The charge control circuit includes a signal mixer circuit receiving signals from the body computer and discharge signals of the automotive battery, a charger integrated circuit (IC) and a feedback control circuit for battery both electrically connected to the signal mixer circuit, and a battery charging circuit electrically connected to the charger IC and transmitting charge signals to the feedback control circuit for battery and the automotive battery. Thereby a conventional dummy load resistor is replaced by the automotive battery for protecting the automotive LED light from overheating, increasing product stability and recycling a part of electricity for recharge of the automotive battery.

A load control device for controlling power delivered from an AC power source to an electrical load may comprise a thyristor, a gate current path, and a control circuit. The control circuit may be configured to control the gate current path to conduct a pulse of gate current through a gate terminal of the thyristor to render the thyristor conductive at a firing time during a half-cycle of the AC power source. The control circuit may operate in a first gate drive mode in which the control circuit renders the gate current path non-conductive after a pulse time period from the firing time. The control circuit may operate in a second gate drive mode in which the control circuit maintains the gate current path conductive after the pulse time period during the half-cycle.

A load control device for controlling power delivered from an AC power source to an electrical load may comprise a thyristor, a gate current path, and a control circuit. The control circuit may be configured to control the gate current path to conduct a pulse of gate current through a gate terminal of the thyristor to render the thyristor conductive at a firing time during a half-cycle of the AC power source. The control circuit may operate in a first gate drive mode in which the control circuit renders the gate current path non-conductive after a pulse time period from the firing time. The control circuit may operate in a second gate drive mode in which the control circuit maintains the gate current path conductive after the pulse time period during the half-cycle.

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.

An apparatus for an LED driver with a silicon-controlled dimmer, can include: a bleeder circuit coupled to a DC bus of the LED driver; and a controller configured to control the bleeder circuit to draw a bleeder current from the DC bus when a conduction angel of the silicon-controlled dimmer is less than an angle threshold, in order to maintain a conduction state of the silicon-controlled dimmer.

An apparatus for an LED driver with a silicon-controlled dimmer, can include: a bleeder circuit coupled to a DC bus of the LED driver; and a controller configured to control the bleeder circuit to draw a bleeder current from the DC bus when a conduction angel of the silicon-controlled dimmer is less than an angle threshold, in order to maintain a conduction state of the silicon-controlled dimmer.

Disclosed are an LED dimming circuit, a dimming device and a dimming method. The LED dimming circuit comprises a reference voltage source, a line voltage compensation module, a dimming module, and a constant current source module. The line voltage compensation module outputs a compensation information to the reference voltage source according to a current line voltage, the reference voltage source modulates a reference voltage according to the compensation information, and then outputs a voltage reference having the compensation information to the dimming module, the dimming module outputs, according to the voltage reference having the compensation information and an externally input dimming signal, a dimming voltage to the constant current source module, the constant current source module controls a working current of an LED lamp string according to the dimming voltage.

Disclosed are an LED dimming circuit, a dimming device and a dimming method. The LED dimming circuit comprises a reference voltage source, a line voltage compensation module, a dimming module, and a constant current source module. The line voltage compensation module outputs a compensation information to the reference voltage source according to a current line voltage, the reference voltage source modulates a reference voltage according to the compensation information, and then outputs a voltage reference having the compensation information to the dimming module, the dimming module outputs, according to the voltage reference having the compensation information and an externally input dimming signal, a dimming voltage to the constant current source module, the constant current source module controls a working current of an LED lamp string according to the dimming voltage.

System and method for controlling one or more light emitting diodes. For example, the system includes: a current regulator including a first regulator terminal and a second regulator terminal, the first regulator terminal being configured to receive a diode current flowing through the one or more light emitting diodes, the current regulator being configured to generate a sensing signal representing the diode current, the second regulator terminal being configured to output the sensing signal; a bleeder controller including a first controller terminal and a second controller terminal, the first controller terminal being configured to receive the sensing signal from the second regulator terminal, the bleeder controller being configured to generate a first bleeder control signal based at least in part on the sensing signal, the second controller terminal being configured to output the first bleeder control signal.