Devices and techniques for individual control of multiple light emitting diodes (LEDs) in a LED array. A LED array may include multiple strands of LEDs with each strand including a single LED or multiple LEDs. The techniques of this disclosure include a parallel approach to controlling a LED array with a current measurement circuit in each LED strand. The current measurement circuits may be selectable by a controller via a multiplexer (MUX). The arrangement of circuit elements provides for an improved initialization phase and operating phase and may achieve an accurate and substantially equal current at all LEDs. The current control may ensure a homogenous light output that accounts for process and production variability, as well as changes in operating conditions. A LED control circuit of this disclosure may also include system safety features including temperatures sensing, and over voltage and over current sensing and protection.

A circuit module for synchronizing the driving of an electrical device module with a second electrical device of a second circuit module is provided. The module includes the electrical device designed to assume a first and a second state, a control unit for controlling the electrical device, wherein the control unit is designed to provide a control signal, depending on which control signal the electrical device changes from the first state to the second state, and a trigger line coupled to the control unit, via which the control unit is couplable to the second control unit of the second circuit module. A synchronization signal is providable at the second control unit by the control unit via the trigger line, which synchronization signal is correlated with the control signal for initiating at least one change of the electrical device from the first to the second state.

Disclosed is an LED lighting apparatus. The LED lighting apparatus may include a leakage current control unit configured to provide a leakage current path when a rectified voltage is retained at a predetermined voltage or less for a preset time or more, and a leakage current and retention current may be discharged through a leakage current path.

LED related lighting methods and apparatus are described. Various features relate to water tight light fixtures. Some of the fixtures are spotlights while other fixture are intended for in ground use. The light fixtures in at least some embodiments include power control features. In spotlight embodiments beam angle and power or light output can be controlled without opening the light assembly or compromising the water tight seals which also protect against dirt. In ground embodiments support tilt angle setting which allow a user to set the light fixture to one or more tilt angles. Beam angle can also be changed in some embodiments as well as power control. Beam angle, power control and tilt angle adjustments are supported in some embodiments but need not be supported in all embodiments with some embodiments using one or more of the described features but not all features.

The invention relates to an LED module (1), comprising: connections (2) for an LED series (3); a circuit (4), which is designed to constitute a load, preferably an active-power load, when a first supply voltage (5a) not equal to zero is applied to the LED module (1), which active-power load is dimensioned in such a way that, when an LED series (3) is connected, said LED series is not conductive, and which is designed to constitute no load when a second supply voltage (5b) not equal to zero is applied to the LED module (1), for which second supply voltage, when an LED series (3) is connected, said LED series is conductive and light is emitted, wherein the type of load change is selected in dependence on the value of the first supply voltage and/or a modulation of the first supply voltage.

LED related lighting methods and apparatus are described. Various features relate to water tight light fixtures. Some of the fixtures are spotlights while other fixture are intended for in ground use. The light fixtures in at least some embodiments include power control features. In spotlight embodiments beam angle and power or light output can be controlled without opening the light assembly or compromising the water tight seals which also protect against dirt. In ground embodiments support tilt angle setting which allow a user to set the light fixture to one or more tilt angles. Beam angle can also be changed in some embodiments as well as power control. Beam angle, power control and tilt angle adjustments are supported in some embodiments but need not be supported in all embodiments with some embodiments using one or more of the described features but not all features.

A load control device for controlling the intensity of a lighting load, such as a light-emitting diode (LED) light source, may include a power converter circuit operable to receive a rectified AC voltage and to generate a DC bus voltage, a load regulation circuit operable to receive the bus voltage and to control the magnitude of a load current conducted through the lighting load, and a control circuit operatively coupled to the load regulation circuit for pulse width modulating or pulse frequency modulating the load current to control the intensity of the lighting load to a target intensity. The control circuit may control the intensity of the lighting load by pulse width modulating the load current when the target intensity is above a predetermined threshold and control the intensity of the lighting load by pulse frequency modulating the load current when the target intensity is below the predetermined threshold.

A load control device for controlling the intensity of a lighting load, such as a light-emitting diode (LED) light source, may include a power converter circuit operable to receive a rectified AC voltage and to generate a DC bus voltage, a load regulation circuit operable to receive the bus voltage and to control the magnitude of a load current conducted through the lighting load, and a control circuit operatively coupled to the load regulation circuit for pulse width modulating or pulse frequency modulating the load current to control the intensity of the lighting load to a target intensity. The control circuit may control the intensity of the lighting load by pulse width modulating the load current when the target intensity is above a predetermined threshold and control the intensity of the lighting load by pulse frequency modulating the load current when the target intensity is below the predetermined threshold.

Surge protection device having surge protection and overvoltage protection capability are provided. In on example embodiment the surge protective device can include a surge protection circuit. The surge protection device can include an over voltage protection circuit coupled in series with the surge protection circuit. The overvoltage protection circuit can include a voltage sensing circuit associated with a voltage threshold one or more switching elements and/or a gating circuit coupled to the voltage sensing circuit. The gating circuit can be configured to control the one or more switching elements to be in a non conducting state when the voltage sensing circuit detects a voltage that exceeds the voltage threshold.

An anti-flicker and anti-glow switchable load apparatus to be installed in the light socket of a commonly powered electronic switching device, such as a motion activated light switch. An energy efficient light bulb or lamp, such as a cathode fluorescent lamp or light emitting diode is then electrically connected to the apparatus. A first embodiment of the present invention includes a switchable light source, a switchable load, a controller, and a voltage sensor. When the present invention in the first embodiment detects a higher voltage, thus indicating the lamp has been switched from the off state to the on state, the switchable load is disconnected, and the current is re-routed to pass through the energy efficient lamp.