Abstract: A standby electric power cutoff apparatus for an electronic product is disclosed.

Abstract: A switching converter includes: an output circuit including a switching transistor, an inductive element, and a rectifying element configured to rectify a current flowing to the inductive element; a control circuit having a monitor terminal, and configured to drive the switching transistor such that a voltage of the load becomes close to a reference voltage when a voltage of the monitor terminal is higher than the reference voltage, and to drive the switching transistor such that a voltage of the load becomes close to a voltage of the monitor terminal when a voltage of the monitor terminal is lower than the reference voltage; and an abnormality protection circuit configured to monitor a state of the load, the control circuit, peripheral circuits, and the switching converter, and to pull down a voltage of the monitor terminal to a voltage lower than the reference voltage when abnormality is detected.

Abstract: The lighting device includes a controller for determining first, second, and third desired values of first, second, third drive currents to first, second, and third light sources, based on a correction coefficient for correcting chromaticity points of the first, second, and third light sources to first, second, and third chromaticity points. The first, second, and third light sources have first, second, and third ranges of individual differences in color. The first chromaticity point is an intersection of a straight line touching the first and second ranges and another straight line touching the first and third ranges. The second chromaticity point is an intersection of a straight line touching the second and first ranges and another straight line touching the second and third ranges. The third chromaticity point is an intersection of a straight line touching the third and first ranges and another straight line touching the third and second ranges.

Abstract: An integrated power module packaging structure includes a housing, a first circuit board, a second circuit board, a first pin, a second pin and a third pin. The housing has a cavity. The second circuit board is located above the first circuit board, and both them are received in the cavity. A switching module is disposed on the first circuit board. A high side current/voltage detecting device and a driving device are disposed on the second circuit board. The first pin, the second pin and the third pin are disposed between the first circuit board and the second circuit board. The first pin connects the high side current/voltage detecting device and the switching module in series. The second pin connects the switching module. The driving device controls the switching module through the third pin.

Abstract: Systems, methods, and devices for a networked lighting system are described herein. One system includes a controller for a networked lighting system, comprising, a memory and a processor configured to execute executable instructions stored in the memory to receive, from an image sensor, positions of a number of luminaires in a networked lighting system of a building. The controller further configured to create a lighting map of the networked lighting system based on the received number of luminaire positions and change an address assigned to at least one of the number of luminaires based on the lighting map.

Abstract: A lighting control circuit for an illuminating lamp includes: a rectifier part that is connected to a ballast to which commercial alternating-current electric power is supplied, and converts the alternating current to direct current; a smoothing capacitor that is provided on an output side of the rectifier part, and removes an alternating-current component included in direct current outputted from the output side; a drive circuit that has a switching element, and performs on-off control on electric current flowing to a plurality of solid-state light-emitting elements connected in series to both ends of the smoothing capacitor; and an inductor that is provided in an electric power supply system between the ballast and the smoothing capacitor.

Abstract: A Solid State Lighting fixture (SSL fixture) for illuminating a desired area, includes an SSL light engine having a plurality of SSL elements that can be activated or dimmed in response to set time and date schedules to illuminate the desired area and a wireless module integrated with the SSL light engine and used for communicating with a remote controller using a wireless network.

Abstract: Illumination devices with improved color mixing optics are disclosed herein for mixing the colors produced by a multi-colored LED emitter module to produce uniform color throughout the entire beam angle of the output light beam, along with smoother edges and improved center beam intensity. Embodiments disclosed herein include a unique arrangement of multi-color LEDs within an emitter module, a unique exit lens with different patterns of lenslets on opposing sides of the lens, and other associated optical features that thoroughly mix the different color components, and as such, provide uniform color across the output beam exiting the illumination device. Additional embodiments disclosed herein include a unique arrangement of photodetectors within the primary optics structure of the LED emitter module that ensure the optical feedback system properly measures the light produced by all similarly colored emission LEDs.

Abstract: A dimmable LED illuminant system is provided, comprising at least two LED illuminant chains connected in parallel and/or back-to-back and having in each case at least one light emitting diode, wherein the LED illuminant system has a control unit and is fed via a supply, which is designed to receive dimming information supplied via the supply and to switch on and/or off in stages individual ones of the LED illuminant chains connected in parallel/back-to-back depending on the supplied dimming information and for the implementation thereof.

Abstract: Circuits and methods for driving an LED from a secondary side of a transformer are disclosed herein. An embodiment of the method includes monitoring an input voltage to determine the power level intended to drive the LED. The current flow through the primary side of the transformer is adjusted to make the power actually driving the LED equal to the power intended to drive the LED.

Abstract: A constant-voltage drive device capable of adjusting output voltage includes a chopping wave structure, an AC power voltage detection module, an AC voltage signal bias module, a power factor correction controller with multiplier, a power factor correction and energy conversion and transmission module, an output control module, a reference signal generation module, an AC power phase angle detection module and a phase angle information transmission module. The output voltage can be both constant and adjustable, so that the output changes with the phase angle information of input, and also provides the chopping wave structure with current for proper functioning. The device is applicable for bigger power range with better compatibility and stronger adaptability.

Abstract: A spectrometer includes a spectrogram, digital camera and signal processing to compensate for limits of system spatial resolution, spatial distortions and lack of precision spatial registration, limited dynamic range, The spectrogram is captured by a digital camera, and the corresponding image is converted to a wavelength and magnitude with mitigation of optical point spread function and potential magnitude clipping due to over-exposure. The clipped portions of the signal are reconstructed using tangential adjacent point spread functions as a reference or adjacent channel ratios as reference. Multichannel camera detectors having unique response magnitude ratios per wavelength are exploited to make associated direct mappings, thereby making improvements in wavelength resolution and accuracy to up to at least one to two orders of magnitude.

Abstract: A light-emitting diode (LED) lamp which can replace a typical fluorescent lamp is provided. The LED lamp comprises external connection pins connected to terminals of an electronic or magnetic fluorescent lamp ballast, capacitor pairs connected to each of the external connection pins, diodes connected to each of the capacitor pairs and a LED array connected between the diodes, wherein an first external connection pin, a first capacitor pair, a first diode, an LED array, a second diode, a second capacitor pair and a second external connection pin are connected in series. Here, the first and second capacitor pairs include capacitors connected back to back. The LED lamp also further comprises a diode connected in anti-parallel with a series circuit of the second diode and the LED array, and another diode connected in anti-parallel with a series circuit of the first diode and the LED array.

Abstract: A solid state light fixture includes a light emitting diode (LED) load and a driver circuit that selectively provides one of a switched-mode drive current and a linear-mode drive current to the LED load in response to a dimming control signal.

Abstract: The present disclosure is directed generally to lighting control, and more particularly, to various inventive methods, systems, computer-readable media (transitory and non-transitory) and apparatus for conveying aggregate presence information using light. For example, in some embodiments, output of a presence sensor over time may be aggregated, and an LED node may cause one or more LEDs to emit light having a property that conveys the aggregated captured output.

Abstract: A wireless lighting control module for LED lighting includes a Zigbee wireless receiver receiving an input wireless control signal, an analog control output which conforms to the 0-10V format, and a microcontroller which is connected to the wireless receiver and receives the input wireless control signal from the wireless receiver. The microcontroller regulates the analog control output. The analog control output has a predetermined cutoff level. A lighting power output is controlled by the microcontroller and cut off by opening a relay when the analog control output is below the predetermined cutoff level. The predetermined cutoff level of the analog control output is 0.5V.

Abstract: An LED driver circuit is provided with a dynamic operating range which can be set using an offline tuning interface. During an offline mode of operation, the tuning interface may be coupled to the dimming control interface and provide both power and one or more digital pulses corresponding to a desired maximum output voltage and/or maximum output current. The controller then modifies the programmed maximum output voltage and the maximum output current values based on the one or more digital pulses received via the tuning interface circuit. Group tuning is permitted by way of a shared bus between a programming device and a plurality of LED driver circuits. Tuning confirmation or error may be detected by an LED driver circuit and the programming device may be notified of the success or failure of a particular tuning operation.

Abstract: An LED backlight driving circuit is disclosed. The present disclosure relates to the technical field of display, whereby the technical problem of the incorrect detection of the short circuit detection module when the open circuit malfunction occurs to one LED backlight unit and the output voltage of the LED backlight driving circuit rises can be solved.

Abstract: A technique for controlling order of selecting elements from an ordered set of N elements, the technique provides applying to the ordered set a mathematical function P converting the order, in which the elements are preliminarily ordered in the set, into a desired order defined by the function P. The elements may further be selected from the set according to the new order defined by the function P. The elements in the set comprise at least one of the following: devices, items, parameters, values.

Abstract: A light emitting element drive apparatus capable of outputting the lowest voltage satisfying drive conditions and having high light emitting efficiency and low power loss, and a portable apparatus using the same, comprising an LED drive apparatus to which LEDs of different drive voltages required for emitting light are connected in parallel and driving one or more LEDs, wherein the LED drive apparatus 10 has drive circuits connected to the corresponding LEDs among a plurality of LEDs and driving the corresponding LEDs with luminances based on set values and power supply circuits for deciding a drive voltage value required for the highest light emission among one or more LEDs driven to emit light based on drive states of drive circuits (for example terminal voltages of the current source) and supplying a drive voltage having at least the decided value to LEDs in parallel.

Abstract: The invention relates to a method for controlling an LED load. First an input voltage is supplied to an inductive element. Subsequently, a current is drawn through the inductive element for a first predetermined time period. Finally, a current is supplied from the inductive element to a first terminal of the LED load during a second time period. The first predetermined time is controlled to maintain a predetermined average current through the LED load.

Abstract: A solid state lighting apparatus can include a variable color input signal configured to indicate a target color of light output from the apparatus. A string current Pulse Width Modulation (PWM) controller circuit can be coupled to the variable color input signal, where the string current PWM controller circuit can be configured to generate a plurality of PWM signals having respective variable duty cycles to enable/disable respective particular string currents for respective variable times as the variable color input signal changes.

Abstract: Lighting control interface techniques and corresponding circuitry are provided. The techniques include receiving a first signal potentially representative of a first lighting control signal, and receiving a second signal potentially representative of a second lighting control signal, and determining if either of the first and second signals complies with a first or second lighting control protocol. The lighting control signal may be applied to the same interface connector (regardless of the protocol), thereby eliminating the need for separate dedicated interface connectors. In some cases, the techniques further include determining that a dummy control signal is manifesting in the first and/or second signals, thereby indicating that no lighting control signal is being applied. Depending on the resulting determination, the techniques may include, for example, setting output lighting power according to a pre-established value, or according to the first or second lighting control protocol.

Abstract: A power circuit for an LED lighting device including an AC power supply, a dimmer and a control circuit is provided. The control circuit includes a filtering unit configured to filter a voltage signal coming from the dimmer and a rectifying unit configured to receive the signal outputted from the filtering unit and rectify the signal to a DC signal. The control circuit also includes a transformer unit connected to the rectifying unit. Further, the control circuit includes a dimmer phase detection unit configured to sample the rectified voltage signal at point K and convert the voltage signal to a low voltage pulse signal and a flyback conversion unit configured to receive the pulse signal outputted by the dimmer phase detection unit and adjust a current flowed through the transformer unit and a first transistor to control the output current to the LED lighting device.

Abstract: Some embodiments include a remote for gesture recognition for an external light system. In some embodiments, the remote may include an acceleration sensor; a wireless transceiver; memory; and a processor communicatively coupled with the acceleration sensor, the wireless transceiver, and the memory. In some embodiments, the processor may be configured to: sample acceleration data from the acceleration sensor; determine a first event type based on the acceleration data; determine a second event type based on the acceleration data; determine a command for an external system based on the first event type; and transmit the command to the external device using the wireless transceiver. In some embodiments, the first event type and/or the second event type comprises an event selected from the list consisting of a swipe, a tap, a double tap, a directional point, and a tilt; exclude the second event type.

Abstract: A light-emitting device having a cover (1), a heat sink (2) and a light-emitting assembly (3), wherein the heat sink (2) has at least one first locking part (a), the cover (1) has at least one second locking part (b) corresponding to the first locking part (a), the second locking part (b) engages with the first locking part (a) to form an enclosed cavity (5) for the light-emitting assembly (3), and the second locking part (b) has a pressing part (b1) pressing the light-emitting assembly (3) against the heat sink (2).

Abstract: A DC supply unit includes a first current blocking device arranged to allow current to flow in a first direction through the first current blocking device, and to block current that flows in a second direction opposite the first direction. In this context, the first direction is the flow direction of current during normal operation of the DC supply network. The DC supply unit further includes a first switching unit arranged in anti-parallel connection with the first current blocking device, wherein the first switching unit is controllable in its on-state to selectively allow reverse current during normal operation of the DC supply network to flow through the first switching unit in the second direction so as to bypass the first current blocking device and in an off-state to block current in the second direction when a fault occurs in the DC supply network.

Abstract: A discharge lamp driving device includes: a discharge lamp drive unit configured to supply a drive current to a discharge lamp having two electrodes; a voltage detection unit configured to detect an inter-electrode voltage of the discharge lamp; and a control unit configured to control the discharge lamp drive unit, wherein the control unit executes first measurement drive in which a polarity of the drive current is maintained constant at a first polarity, the voltage detection unit measures the inter-electrode voltage multiple times in a first measurement period in which the first measurement drive is executed, and the control unit determines states of the electrodes of the discharge lamp based on a plurality of the inter-electrode voltages measured in the first measurement period.

Abstract: An LED driver circuit is provided with a dynamic operating range which can be set using an offline tuning interface. During an online mode of operation, a controller for a power converter is configured to regulate the output voltage and the output current generated by the power converter based on a dimming control signal from a dimming control interface, a sensed output from the power converter, and programmed maximum output voltage and maximum output current values. During an offline mode of operation, the tuning interface may be coupled to the dimming control interface and provides a sequence of digital pulses corresponding to a desired maximum output voltage, maximum output current, or operating parameter. The controller then modifies the programmed maximum output voltage and the maximum output current values based on the predetermined sequence of digital pulses received via the tuning interface circuit.

Abstract: A light fixture can include at least one light fixture component comprising at least one light source that emits a first level of fixture light. The light fixture can also include at least one sensor that measures a first total light amount at a first time of a first day, where the first total light amount includes the first level of fixture light and a first natural light amount. The light fixture can further include a controller coupled to the at least one sensor and the at least one light fixture component, where the controller controls and communicates with at least one sensor. The controller can further control the at least one light fixture component based on the first total light amount measured by the at least one sensor at the first time of the first day.

Abstract: The present invention provides a programmable continuous wave high power laser diode system, which comprised digital control unit, a switch module unit, and a latch current controlling unit so as to provide user to set the latch current of the high power laser diode via the digital control unit controlling the switch module unit and the latch current controlling unit, therefore, the laser diode system includes advantages of high system efficiency, reliability, low output ripple current range and fast switching reaction time.

Abstract: In some implementations, a device includes a first full bridge rectifier configured to receive power from an alternating current (AC) power source, the first full bridge rectifier having direct current (DC) output nodes, a second full bridge rectifier configured to receive power from the AC power source, the second full bridge rectifier having DC output nodes, wherein the second full bridge rectifier is coupled to receive AC power in series with the first full bridge rectifier, a first set of light emitting diodes coupled to the DC output nodes of the first full bridge rectifier, and a second set of light emitting diodes coupled to the DC output nodes of the second full bridge rectifier.

Abstract: Various embodiments for conducting proxy teaching for learning devices within a decentralized system, including an embodiment method with operations for obtaining, by a teacher signaling device, objectives data related to activities of one or more of the learning devices, generating, by the teacher signaling device, teaching routines based on the obtained objectives data, and broadcasting, by the teacher signaling device, teaching signals configured to teach one or more of the learning devices based on the generated teaching routines. Other embodiments may obtain objectives data by requesting reflex information from the learning devices or intercepting event report messages transmitted by the learning devices. Other embodiments may include broadcasting discovery signals to identify nearby learning devices and modifying teaching routines when objectives of the generated teaching routines cannot be achieved.

Abstract: A control system for a light emitting diode (LED) driver is provided. The control system includes a control module, a command interface, and a combined signal interface. The control module includes a microcontroller configured to receive at least one signal and to determine an LED driver command signal and a command module connected to the microcontroller and capable of communicating with both the lighting dimmer and the wireless control module. The control system includes a command interface which communicatively couples the control module to the LED driver. A combined signal interface communicatively couples the command module and at least one of the lighting dimmer and the wireless control module. The combined signal interface conveys one or more signals between the control module and at least one of the lighting dimmer and the wireless control module. Associated methods and modules are also provided.

Abstract: A circuit arrangement includes a converter having a converter switch and a driver for the converter switch. The driver includes an interface coupling to a dimming apparatus supplying a dimming value. The driver provides an RF signal with a duty ratio at the output of the driver. The driver modifies the RF signal by superposition of a PWM signal such that, in correlation with the supplied dimming value, a predefinable number of periods of the RF signal is chopped from the RF signal. The driver is configured to reduce the duty ratio of the RF signal during at least one predefinable period of the RF signal in order to adjust levels of dimming which correspond to dimming values which are between a first and a second dimming value which differ from one another by at least one period of the RF signal.

Abstract: In exemplary embodiments of this invention, one or more I/O devices accept input from a human user. The input is indicative of a value for each control variable in a set of separate control variables. A computer analyzes the input and outputs control signals to specify a set of separate setpoints. Dimmers adjust the intensity or color of a set of luminaires according to the setpoints. The number of separate control variables is much less than the number of separate setpoints. Having a human control a small number of control variables, in order to control a much larger number of separate luminaire setpoints of luminaires, has at least two advantages: control is faster and control is more intuitive. In illustrative implementations, the luminaire setpoints that are being controlled are not functions of each other.

Abstract: Controlling the color temperature of a composite light source including at least one discrete-spectrum light source is disclosed. For example, the color temperature of a composite light source including at least one discrete-spectrum light source may be determined and/or adjusted based on one or more of the ambient color temperature of a space, the actual temperature of the space, the relative brightness of the space, the occupancy of the space, a time clock, a demand response command (e.g., from an electrical utility), the absolute location of the composite light source, the location of the composite light source relative to other light sources, inputs from a camera or other external devices, the operation of appliances or other machines in the vicinity of the composite light source, media content being utilized in the vicinity of the composite light source, and/or other sensor inputs.

Abstract: A lighting system uses an array of lighting elements which provide light in different directions. The intensity of the lighting elements is controlled in dependence on a time-varying parameter related to at least one of a position of a light emitting or light reflecting body, and an intensity, color or color temperature of the light emitted or reflected by the body, such that the system can simulate directional sunlight.

Abstract: A light emitting element failure detector (4) includes a light emitting element (1), a constant current circuit (2) which supplies an electric current to the light emitting element (1), and an electric discharge path which discharges an electric charge such as the light emitting element (1). A light emitting element failure detector (4) further includes an instantaneous current interruption circuit (5) which instantaneously interrupts an electric current to the light emitting element (1) by a current supply path different from the electric discharge path, a diode (60), a DC power supply (61), and a current detector (62). The DC power supply (61) generates a direct-current reference voltage having a positive value lower than a voltage between the anode and cathode of the light emitting element (1) in a normal state. The DC power supply (61), the diode (60), and the current detector (62) which are connected in series constitute a parallel electric path of the light emitting element (1).

Abstract: Apparatuses, methods and storage medium associated with an intelligent LED light apparatus are disclosed herein. In embodiments, an intelligent LED light apparatus may include a communication interface, a processor, a body that encases at least the communication interface and the processor, and a plurality of sensors of a plurality of sensor types disposed on the body. The processor may be configured to receive sensor data from the sensors, and transmit the sensor data or results from processing the sensor data to an external recipient. Further, for some embodiments, the intelligent LED bulb apparatus may further comprise LED lights, and the body further encases the LED lights. In other embodiments, the body may include a male connector to mate with a bulb receptor, and a female connector to mate with a LED bulb. Other embodiments may be disclosed or claimed.

Abstract: A device for driving several light sources is provided, wherein the several light sources are arranged in a light matrix structure, the device comprising a common circuitry and a driver matrix; wherein each cell of the driver matrix is connected to at least one cell of the light matrix structure; wherein a sense component is provided on a cell of the driver matrix, wherein the sense component determines a sense signal that is based on, and in particular dependent on or proportional to, an output signal driving the light source that is connected to this cell of the driver matrix; wherein the common circuitry comprises an adjustment circuitry that is arranged for obtaining the sense signal, for adjusting a reference signal, and for conveying the reference signal to the cell of the driver matrix that determined the sense signal; wherein the cell of the driver matrix is arranged for adjusting the output signal driving the light source based on the reference signal. Also, an according method is suggested.

Abstract: LED modules are disclosed having a control MOSFET, or other transistor, in series with an LED. In one embodiment, a MOSFET wafer is bonded to an LED wafer and singulated to form thousands of active 3-terminal LED modules with the same footprint as a single LED. Despite the different forward voltages of red, green, and blue LEDs, RGB modules may be connected in parallel and their control voltages staggered at 60 Hz or greater to generate a single perceived color, such as white. The RGB modules may be connected in a panel for general illumination or for a color display. A single dielectric layer in a panel may encapsulate all the RGB modules to form a compact and inexpensive panel. Various addressing techniques are described for both a color display and a lighting panel. Various circuits are described for reducing the sensitivity of the LED to variations in input voltage.

Abstract: A method for controlling at least one lighting element includes: setting a dimming speed; determining a dimming level according to the dimming speed; and using the dimming level to perform a stepped dimming operation to brighten or dim the lighting element.

Abstract: A system and method includes a controller that alternately enables at least two different current paths for a current flowing through a dimmer when the dimmer is in an OFF mode. In at least one embodiment, enabling and disabling the current paths allows a power supply of the dimmer to continue functioning and provides the controller sufficient voltage to continue functioning. One of the current paths is a low impedance path and another current path is a path to a voltage supply node of a switching power converter controller. In at least one embodiment, the controller generates an impedance control signal to enable a low impedance current path for a current in the dimmer and alternately provide a current path to the voltage supply node for the controller.

Abstract: This disclosure describes systems, methods, and apparatus for an LED driver circuit capable of responding to dimmer signals from three different types of dimmers: a phase cut dimmer, a dedicated dimmer (e.g., 0-10V dimmer), and a button dimmer. The processor can include inputs for each of these dimmer types, and can be configured to determine which of the three types of dimmers is controlling the LED driver circuit, and determine which dimming signals to respond to when more than one dimmer type is trying to control the LED.

Abstract: An illumination device comprising a plurality of light emitting diodes (LEDs) and a method for calibrating the illumination device is provided herein. According to one embodiment, the method may include subjecting a first LED to a first ambient temperature, measuring a forward voltage developed across the first LED upon applying a relatively small drive current to the first LED, detecting at least a first, a second and a third luminous flux output from the first LED upon successively applying at least a first, a second and a third drive current to the first LED, and storing results of the measuring and detecting steps within the illumination device to calibrate the first LED at the first ambient temperature. In some embodiments, the first LED may be subjected to a second ambient temperature, which is different from the first ambient temperature, and the method may repeat the steps of measuring, detecting and storing to calibrate the first LED at the second ambient temperature.

Abstract: An arrangement and a method for controlling a plurality of light emitting diodes which are connected in series to attain uniform distribution of a total current to several series connections, LED chains, connected in parallel to each other wherein circuitry-related expenditure and power losses occurring during the control process are minimized, include a first reference voltage generating unit and a second reference voltage generating unit, wherein a outlet of the first reference voltage generating unit is connected to a first and a second control circuit, and an outlet of the second reference voltage generating unit is connected to the second and the first control circuit, and an outlet of the first control circuit is connected to a control inlet of the first controllable semiconductor switch, and an outlet of the second control circuit is connected to a control inlet of the second controllable semiconductor switch.

Abstract: The present disclosure relates to LED driving circuit and method using a single inductor. A constant current controller controls a power stage circuit to provide a constant output signal, and thus to provide a constant current signal for an LED load. A dimming controller regulates luminance of the LED load. A constant voltage generating circuit receives the current signal at an output terminal of the power stage circuit and a reserve supply voltage for providing a supply voltage for the dimming controller. Compared with the prior art, the present disclosure does not need an independent power supply chip, and reduces components such as inductors and rectifying transistors. Thus, a peripheral circuit is simplified, and an overall size of the system is reduced.

Abstract: A two-level LED security light with a motion sensor. At night, the LED is turned on for a low level illumination. When the motion sensor detects any intrusion, the LED is switched from the low level illumination to a high level illumination for a short duration time. After the short duration time, the LED security light returns to the low level illumination for saving energy. The LED security light includes a power supply unit, a light sensing control unit, a motion sensing unit, a loading and power control unit, and a lighting-emitting unit. The lighting-emitting unit includes one or a plurality of LEDs which may be turned-on or turned-off according to the sensing results from the light sensing control unit. When the motion sensing unit detects an intrusion, the illumination of the LED security light can be immediately turned on to the high level to scare away the intruder.

Abstract: A two-level LED security light is operated with a motion sensor. When an electric power is supplied, the LED security light is turned on for a low level illumination. When the motion sensor detects any intrusion, the LED security light is switched from the low level illumination to a high level illumination for a short duration time to scare away the intruder. After the short duration time, the LED security light returns to the low level illumination for saving energy. The LED security light includes a power supply unit, a motion sensing unit, a loading and power control unit, and a lighting-emitting unit. The lighting-emitting unit includes one or a plurality of LEDs which may be turned-on or turned-off by control signal generated from the loading and power control unit.