Abstract: The present invention provides a power control circuit which has a timing unit used for timing an elapsed time of current half cycle of the phase-cut AC power supply signal, outputting a current accumulated timing duration, and outputting a first control signal at a starting moment when a starting point of a half cycle of the AC power supply signal is detected; a regulating unit connected to the timing unit and comprising a temporary storage module, wherein a final reference time interval is stored in the temporary storage module, and when the current accumulated timing duration reaches the final reference time interval, the regulating unit outputs a second control signal; and a control unit connected to the detection unit and the regulating unit and used for controlling current in a load based on the first control signal and the second control signal.

Abstract: For a buck-boost DC-DC converter with n-type high-side field effect transistor (HSFET), a supply is derived from input and output rails, and this supply maintains a constant differential voltage independent of input supply voltage. The derived supply is used as the high supply (HS) of an HSFET Driver. As such, the HSFET resistance becomes independent of supply variation. A wide range ultra-low IQ (Quiescent current), edge triggered level-shifter provides support to a bootstrapped power stage of the inverting buck-boost DC-DC converter. When p-type HSFET is used, a supply is derived from the input and output supply rails, and this derived supply maintains a constant differential voltage independent to the input supply voltage. The derived supply is used as the low supply (LS) or ‘ground’ of the HSFET Driver. As such, the p-type HSFET resistance becomes independent of supply variation.

Abstract: 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.

Abstract: Disclosed are a lamp control system and a control method thereof. The lamp control system includes: an LED light source assembly, an AC input end, an on-off switch, an EMI filter circuit, a rectifier filter circuit, a buck circuit, a rectifier output circuit, a voltage stabilizing circuit, and a control circuit; the EMI filter circuit is connected to the AC input end through the on-off switch; the EMI filter circuit, the rectifier filter circuit, the buck circuit, and the rectifier output circuit are electrically connected in sequence; the rectifier filter circuit, the voltage stabilizing circuit, the control circuit, and the buck circuit form a closed-loop circuit, the rectifier output circuit is electrically connected to the LED light source assembly.

Abstract: A load control device for an electrical load is configured to operate in a normal mode and a burst mode to adjust the amount of power delivered to the electrical load. The load control device comprises a control circuit that operates in the normal mode to regulate an average magnitude of a load current conducted through the load between a maximum rated current and a minimum rated current. During the normal mode, the control circuit controls the operating period of a load regulation circuit between a high-end operating period and a low-end operating period. The control circuit operates in the burst mode to regulate the average magnitude of the load current below the minimum rated current. During the burst mode, the control circuit adjusts the low-end operating period to be less than or equal to a minimum on time of the load regulation circuit.

Abstract: An inverter includes a DC/DC converter which converts a direct current received from a DC voltage source into an intermediate circuit voltage of an intermediate circuit, a DC/AC converter which converts the intermediate circuit voltage into an AC voltage, and a monitoring unit which monitors capacitors of the intermediate circuit for protection against overvoltages. If an overvoltage occurs at one of the capacitors of the intermediate circuit the overvoltage unit decouples the DC voltage source from the intermediate circuit by actuating the DC/DC converter.

Abstract: A lighting device according to an embodiment of the present disclosure includes a lighting part which includes a substrate provided along a longitudinal direction of the lighting device and a lighting unit provided on the substrate, and a diffusing part which is provided along the longitudinal direction of the lighting device, accommodates the lighting part therein, and diffuses light generated in the lighting part.

Abstract: An occupancy sensor with integral light level sensors is configured to turn off or disable peripheral circuits and go into a periodic deep sleep mode to reduce phantom loading. Peripheral circuits include occupancy sensor circuits and relay drive circuits, but may include other circuits such as communication circuits. The sensor may be configured to periodically wake itself up, check ambient light conditions to see if lighting is below the set threshold. If it is not, the sensor goes back to sleep. If it is, then the sensor can power up the occupancy sensor circuit to see if the space is occupied; if not, it can go back to sleep. If the space is occupied, it can turn on other peripheral circuits necessary to control the load.

Abstract: A driving system for driving light-emitting modules includes driving current generation modules connected respectively to the light-emitting modules, and a brightness modulation module connected to the current generation modules and the light-emitting modules. Each driving current generation module is configured to receive signals from the brightness modulation module to control a driving current that flows through the light-emitting module it is connected to. The brightness modulation module is configured to generate the signals based on voltages provided at terminals of the light-emitting modules that are connected to the driving current generation modules.

Abstract: A color correction device includes a computation engine including a processor and a memory coupled to the processor. The computation engine is configured to receive reference color data. A software application stored in the memory and configured to compute adjustment values needed to achieve the reference color data from a target color. An output configured to output color corrected signals to light emitting diodes (LEDs) to achieve a reference color associated with the reference color data from the target color of the LEDs.

Abstract: Provided is an optical compensation method for a display device including a pixel coupled between first power and second power sources. In the optical compensation method, the first voltage level of the second power source corresponding to a first luminance level is set while measuring the luminance of the display device, the second voltage level of the second power source corresponding to a second luminance level is set while measuring the luminance of the display device, the third voltage levels of the second power source for representative luminance levels including the first and second luminance levels are set based on the first and second voltage levels, and the fourth voltage levels of the second power source for the representative luminance levels according to temperature conditions are set based on the third voltage levels and temperature offsets according to the temperature conditions, under which the display device is driven.

Abstract: In an initialization method of human-factor lamps capable of intelligently adjusting ambient light, each light emitting device with a Bluetooth transmission function has its corresponding Bluetooth address, and a specialist carries a mobile device with the Bluetooth transmission function to move to the position of each of the light emitting devices. If a detection unit of the light emitting device detects the specialist, an active state will be shown, and the mobile device will select and display the active state and the light emitting device within the Bluetooth detection range, and then the light emitting device corresponding to the active state will show a luminous change, and the specialist can confirm the correct position of the light emitting device by the luminous change and use the pre-set relationship list to confirm the light emitting device and write the corresponding identity code into the light emitting device to complete an initialization.

Abstract: In a method for operating a heating device, fluid is initially introduced into a fluid chamber, then the heating elements of the heating device are switched on and a leakage current is detected as a temperature-dependent current flow through a dielectric insulation layer. A supply voltage of the heating devices is measured and is taken into account in an evaluation of the temperature at the fluid chamber as a function of the leakage current. The leakage current is converted into a leakage voltage by means of a resistor, which is then divided by the measured supply voltage. Subsequently, the quotient obtained may be multiplied by a compensation value in order to obtain a normalized leakage signal, which is normalized to a base value of the supply voltage.

Abstract: The present disclosure provides a control method for an AC-DC conversion circuit. The method includes: in an entire load range, acquiring circuit parameter information of the AC-DC conversion circuit; limiting an actual switching frequency or an actual switching period of the AC-DC conversion circuit within a preset working range according to the circuit parameter information. The AC-DC conversion circuit can meet requirements of Total Harmonic Distortion (THD), Power Factor (PF), efficiency and Electromagnetic Interference (EMI) and the like by adjusting the working information of the AC-DC conversion circuit through the preset working range.

Abstract: Disclosed are a filament device for an illumination device, the illumination device, and a dimming method for the illumination device.

Abstract: An ignition coil has primary and secondary coils, a central core and a pair of split cores. One of the split cores has a first opposing face orthogonal to a coil axial direction X facing a core front end face of the central core in the coil axial direction X. The respective split cores have second opposing surfaces mutually facing each other in a lateral direction Y at a rear end of the central core. At least one of the second opposing surfaces and one of rear end surfaces of the central core contacting the least one of the second opposing surfaces collectively constitute a pair of oblique surfaces and come to close to the other one of the second opposing surfaces in the lateral direction Y as a portion of each of the oblique surfaces recedes further from the first opposing face in the coil axial direction X.

Abstract: A human-factor lamp and system capable of intelligently adjusting ambient light includes light emitting devices, each having a detection unit. When the detection unit detects a human within the lamps sensor field of view one of the light emitting device, such light emitting device is defined as a primary lamp and all others are defined as secondary lamps. The primary lamp is adjusted to a maximum luminous intensity and the secondary lamps are adjusted outwardly from the primary lamp and decremented to a minimum luminous intensity. When any secondary lamp is near more primary lamps away from different distances, the one with a larger luminous intensity is used as a basis for adjusting the brightness after the luminous intensity of the secondary lamp is decremented. In the environment having the human-factor lighting system, the overall ambient luminous performance can be changed according to the moving position of people.

Abstract: Apparatuses, systems and methods for regulating the output currents of a power supply at a target output current include a buck converter module operably connected to a power source and a load. A first switch couples the power source to the buck converter module during a first period of a given operating cycle, while the buck converter module stores and provides electrical power to the load. During a second period, the buck converter may discharge the electrical power stored during the first period. A current sensor senses the currents during at least one of the first period and the second period and, over the operating cycle, the switching is adjusted so the average output current equals the target output current. Adjustments to the first and second period durations result in maximum and a minimum currents symmetrically disposed about the average current provided to the load during the operating cycle.

Abstract: A device for determining a type of a power source for powering a LED lighting unit, wherein one possible type comprises a ballast originally designed for a high intensity discharge lamp and repurposed for use with an LED lighting unit. The power source type determiner monitors at least one electrical parameter of either a load or the power source itself after a power drawn by the load whose characteristic is set to a critical value. A value of the electrical parameter is used to identify a type of the power source. A value of the electrical parameter is the pulse generated by the traditional ballast for gas discharge lamp, which pulse is detected to determine the type of the power source.

Abstract: Systems and methods for using parasitic capacitance of a transformer as an element in a resonant converter are provided. Aspects include determining a parasitic capacitance associated with a transformer, determining a resonant circuit configuration based at least in part on the parasitic capacitance associated with the transformer, and providing a resonant converter comprising the resonant circuit and the transformer.

Abstract: A 2-Wire LED dimming system and method re-purposes existing 120V AC architecture and hardware to carry low voltage PWM gradient DC power to the LED lamps provides a consistent gradation over a 0-100% dimming range. An LED Driver is electrically connected to an AC power source and connect to at least one LED lamp. The AC power source is electrically connected to an AC to DC converter where the AC power is converted to filtered and regulated DC power for the control unit and the power switch. The power switch is electrically connected to the AC to DC converter DC power output. The control unit is electrically connected to the power switch which is turned ON or OFF according to the pulse width modulation PWM signal from the control unit in order to connect or disconnect the DC power from the AC to DC converter.

Abstract: The present disclosure discloses a display driving apparatus in which the consumption power of a chip is optimized through control for each output channel of the chip. The display driving apparatus includes a consumption current control circuit for each output channel. The consumption current control circuit is configured to selectively provide a control current having a high current amount in order to drive an output voltage for the output side of an output buffer in response to a change in the pattern having a great difference between an input voltage and an output voltage.

Abstract: A detection circuit detects at least one of a value of a current flowing through a power transmitting coil, and a value of a current or voltage generated by an auxiliary coil. A control circuit determines a transmitting frequency based on the value detected by the detection circuit, the transmitting frequency at least locally minimizing load dependence. The control circuit determines a voltage for the transmitting power at which an output voltage of a power receiver apparatus is equal to a predetermined target voltage when generating the transmitting power having the transmitting frequency determined, and controls the power supply circuit to generate the transmitting power having the transmitting frequency and voltage determined.

Abstract: A device for image frame capturing, a device for detecting at least one frozen image frame within at least one video stream, a system for providing a frozen image frame detection within at least one video stream, respective methods and vehicle are described.

Abstract: Various implementations disclosed herein includes a method for operating lighting fixtures in horticultural applications. The method may include receiving a user input of a desired irradiance for a first color channel of one or more lighting fixtures that irradiates a plant bed, in which each of the one or more lighting fixtures comprises at least one light emitting diode (LED) array, determining, for each of the one or more lighting fixtures, a PWM setting of the first color channel such that each of the one or more lighting fixtures irradiate the plant bed at the desired irradiance based on calibration data stored in each of the one or more lighting fixtures, and applying, to each of the one or more lighting fixtures, the determined PWM setting of the first color channel.

Abstract: A dimming regulated power supply module comprising a control circuit, a voltage-stabilizing circuit, a dimming circuit, and an output port, wherein the control circuit converts city power into a supply voltage for supplying power to a LED light string through the output port, wherein the voltage-stabilizing circuit senses an internal voltage of the control circuit to generate a first voltage and a second voltage, and supplies power to a single-chip microcomputer in the dimming circuit after stabilizing the second voltage, wherein the voltage-stabilizing circuit outputs the first voltage to set the voltage range of the dimming circuit, wherein the output port transmits the dimming signal output by a dimmer to the dimming circuit, and wherein the dimming circuit generates a corresponding pulse-width modulation signal, wherein the control circuit controls the supply current according to the pulse-width modulation signal, thereby controls the brightness of the LED light string through the output port.

Abstract: Device comprising: a rear panel comprising a network of backlighting elements, a front panel comprising a network of optical valves which are each capable of modulating the brightness of a single primary colour. By the modulation of chrominance which is added to the modulation of luminance for the backlighting elements of the rear panel, the device according to the invention makes it possible to display the images with even more contrast and better quality. A specific control mode makes it possible to avoid the colour “interferences”.

Abstract: A global positioning system (GPS) registration tool (GRT) is provided that is configured to register GPS coordinates of a streetlight controller (SLC) during installation of the SLC at a light fixture and store the GPS coordinates of the SLC at the SLC. Related systems, methods and computer program products are also provided.

Abstract: There is described an emergency lighting system for minimizing power leakage to assure proper operation of an emergency mode. The system comprises a digital addressable lighting bus having digital control lines, a driver, and a lighting control. The driver receives emergency power and provides the emergency power to a light emitter in response to detecting that the digital control lines are shorted. The lighting control receives normal power and includes a relay contact that shorts the digital control lines in response to detecting lack of the normal power. For another aspect, the driver and the lighting control are coupled to lighting control lines, which are either digital or analog control lines. For yet another aspect, a control bypass comprises a power unit, a relay coil, and a relay contact. The relay contact manages outputs of the power unit in response to activation and de-activation by the relay coil.

Abstract: A building management system and method for sensor time correction is described. The system comprises multiple sensors and an energy manager communicating with the sensors. The sensors, distributed within a particular area, provide multiple time measurements in response to detecting an object traversing among the sensors in which the time measurements are associated with unsynchronized time. The energy manager identifies a predicted time for traversing among the sensors based on one or more distances between pairs of sensors and an average velocity of the object to traverse among the sensors. The energy manager determines a sensor time error for each sensor by cross-correlating the time measurements with the predicted time.

Abstract: A turn-off circuit for a semiconductor switch includes an element having a variable resistance coupled to a control input of the semiconductor switch, a circuit for generating a control-input reference signal, and a control circuit coupled to adjust a resistance of the element having a variable resistance in response to the control-input reference signal in a closed control loop in order to turn off the semiconductor switch.

Abstract: A current drive circuit applied in an LED drive circuit that is compatible with a triac dimmer and is configured to generate a direct current bus voltage includes: a current generation circuit configured to receive the direct current bus voltage, and to generate a drive current based on a PWM dimming signal, in order to drive an LED load; and an input current regulation circuit configured to generate a regulation signal based on a duty cycle of the PWM dimming signal, in order to control an operation state of the triac dimmer.

Abstract: A light emitting device is provided. The light emitting device includes a first light emitter comprising a plurality of light emitting elements configured to emit light in a visible light region, a second light emitter comprising a plurality of light emitting elements configured to emit light in an ultraviolet B (UVB) region, and at least one processor configured to control the first light emitter and the second light emitter so that a sum of an intensity of light emitted from the first light emitter and an intensity of light emitted from the second light emitter is greater than or equal to a threshold illuminance value.

Abstract: A system includes a control device and a magnetic device coupled to the control device. The magnetic device is configured to inductively couple to a treatment target including one or more cells exposed to an agent, and includes one or more magnetic coils. The control device and the magnetic device are collectively configured to generate and apply a transient magnetic field to the treatment target to induce an electric field and porate the one or more cells and to permit the agent to enter the one or more cells.

Abstract: Techniques for reducing the risk for an unsafe eye condition associated with light sources. In an example, a light source package is described. The light source package includes a package body defining an interior volume and including an opening. The package also includes a light source contained inside the interior volume of the package body. The package also includes an optical element that occupies at least a portion of the opening of the package body. An electrically conductive material is disposed over a surface of the optical element. This material may be electrically coupled with a system. The system accesses an electrical parameter of the material, determines a damage associated with the optical element based on the electrical parameter, and initiates a corrective action associated with the light source based on the damage.

Abstract: The present invention provides a linear drive energy recovery system, comprising a power source module, a primary working load module, and a secondary working load module, wherein the power source module is connected to the primary working load module, and the secondary working load module is connected in series to the primary working load module such that a voltage provided by the power source module minus a voltage drop caused by the primary working load module is supplied to the secondary working load module as an operating voltage of the secondary working load module.

Abstract: The present disclosure provides an LED straight light including a light tube with two pins at both ends, an LED installed in the light tube and a driving circuit. The driving circuit includes a mains branch and a signal branch. The mains branch is coupled to the pins at one end of the light tube for transmitting power to the LED for power supply. The signal branch is coupled to the pins at the other end of the light tube for transmitting external driving signals to control the on/off of the mains branch. The LED straight light of the present disclosure is powered by two ends, one of the two ends supplies power to the LED through the mains branch, and the other end receives driving signals to control the on/off of the mains branch.

Abstract: One embodiment of the invention relates to a system for operating a plurality of streetlights in response to motion from a vehicle. The system includes a sensor associated with at least one of the streetlights and configured to detect the presence of a moving vehicle and to provide a signal representative of the moving vehicle. The system further includes a radio frequency transceiver associated with each of the streetlights. The system yet further includes processing electronics configured to receive the signal representative of the moving vehicle from the sensor and to cause the radio frequency transceiver to transmit a command to one or more of the plurality of the streetlights to change lighting states along a pathway for the vehicle.

Abstract: A measurement system has an analog channel comprising an analog-to-digital converter for converting an external analog input signal into a corresponding digital input signal, an external trigger input for receiving an external trigger signal comprising a comparator configured to compare the external trigger signal against a trigger threshold signal for generating a binary trigger signal, and a digital signal processing unit. The digital signal processing unit comprises a digital trigger unit configured to receive the digital input signal and to generate at least one trigger event signal based on the digital input signal, and a trigger logic unit configured to receive the at least one trigger event signal and the binary trigger signal to generate a combined trigger signal. Further, a method for generating a trigger signal for a measurement system is described.

Abstract: A power factor calibration circuit includes a multiplier, a boost inductor, an auxiliary winding, a detection resistor, a compensation capacitor, a comparator, and an auxiliary switch. The comparator is configured to detect inductor current flowing through the boost inductor. When the detected inductor current is too small, the energy stored in the compensation capacitor is transmitted to the auxiliary winding for generating compensation current, thereby enhancing the level of the inductor current.

Abstract: A PoDL system that uses a center-tapped transformer, for galvanic isolation of the PHY, has AC-coupling capacitors in series between the transmission wires and the transformer's secondary windings for blocking DC voltages generated by a PSE power supply. The center tap is conventionally connected to ground. As a result, one capacitor sees the full VPSE voltage across it, and the other capacitor sees approximately 0 V across it. Since the effective value of a ceramic capacitor significantly reduces with increasing DC bias voltages across it, the effective values of the capacitors will be very different, resulting in unbalanced data paths. This can lead to conversion of common mode noise and corrupt the data. To avoid this, a resistor divider is used to generate VPSE/2, and this voltage is applied to the center tap of the transformer. Therefore, the DC voltage across each capacitor is approximately VPSE/2, so their values remain equal.

Abstract: Information handling systems, methods, and computer-readable media enable gameplay event detection and gameplay enhancement operations. One or more in-game events may be detected by monitoring audio content, by monitoring video content, by monitoring user input, by monitoring other information, or a combination thereof. The one or more in-game events (and information related to the one or more in-game events) may be stored at a database. Information of the database may be accessed to trigger one or more gameplay enhancement operations. The one or more gameplay enhancement operations may include an automatic highlight capture operation, a dynamic screen aggregation operation, a dynamic position switch operation, a dynamic player switch operation, a gameplay enhancement operation using one or more peripheral devices (e.g., a lighting effect or a haptic feedback event), one or more other gameplay enhancement operations, or a combination thereof.

Abstract: Provided are a display panel, a control method thereof, and a display device. The control method includes: acquiring a correspondence between temperature and voltage information of a first cathode of a first sub-pixel among a plurality of first sub-pixels, a correspondence between temperature and information about a voltage difference between an auxiliary electrode and the first cathode, and current temperature information of the display panel; and determining voltage adjustment information of the first cathode and the auxiliary electrode according to the current temperature information, the correspondence between temperature and the voltage information of the first cathode, and the correspondence between temperature and the information about the voltage difference between the auxiliary electrode and the first cathode so as to adjust the voltage difference between the first cathode and the auxiliary electrode so that a display color purity of the first sub-pixels meets a preset requirement.

Abstract: A lighting control system, including a TRIAC dimmer, a wireless control apparatus, and a lighting apparatus. The lighting apparatus includes a rectifier circuit, a TRIAC dimming detection circuit, a dimming constant-current circuit, and a controller connected to the TRIAC dimming detection circuit and the dimming constant-current circuit. The controller is configured to, control the dimming constant-current circuit to perform dimming on the lighting load based on a brightness control signal, in response to receiving the brightness control signal sent by the wireless control apparatus, and control the dimming constant-current circuit to restore a default state to stop the wireless control apparatus from limiting the dimming constant-current circuit, in response to the TRIAC dimming detection circuit determining that a first preset operation is performed on the TRIAC dimmer.

Abstract: A pixel driving circuit, a pixel unit and a driving method therefor, an array substrate, and a display device for reducing mura phenomenon comprise: a data write sub-circuit for transmitting signals input by the data voltage terminal to a first node; an input and read sub-circuit for transmitting a signal input from a signal transmission terminal to a second node, or reading an electric signal of the second node to the signal transmission terminal; and an output control sub-circuit for transmitting a signal of a first voltage terminal to a drive sub-circuit, and transmitting a driving signal output by the drive sub-circuit to a driven circuit, wherein the drive sub-circuit outputs the driving signal under control of the signal of the first node and the signal of the first voltage terminal.

Abstract: An operating method for a light-emitting diode (LED) power supply includes the following operations: controlling an output voltage to be a first voltage by a control circuit; detecting a load current by a detection circuit; maintaining the output voltage as the first voltage by a constant voltage control circuit when the load current is greater than zero, changing the output voltage from the first voltage to a second voltage by the control circuit when the load current is equal to zero, and the second voltage being greater than the first voltage.

Abstract: A triac dimming system for lighting dimming function includes a triac dimming circuit and a zero-cross test unit. The zero-cross test unit connect with triac dimming circuit and pass the zero-cross signal to triac dimming circuit, then the main control center of triac dimming circuit will adjust the ON/OFF timing of triac dimming unit according to the zero-cross signal and the reserved amount to make the conduction angle of triac dimming circuit stable. After precisely controlling the brightness of the AC lamps, it can keep the AC load (AC lamps) flicker within the acceptable level of the user (no flicker feeling by the naked eye).

Abstract: A load control device for controlling the amount of power delivered to an electrical load is able to operate in a normal mode and a burst mode. The load control device may comprise a control circuit that activates an inverter circuit during active state periods and deactivates the inverter circuit during inactive state periods. The control circuit may operate in the normal mode to regulate an average magnitude of a load current conducted through the electrical load to be above a minimum rated current. The control circuit may operate in the burst mode to adjust the average magnitude of the load current to be below the minimum rated current. The control circuit may adjust the average magnitude of the load current by adjusting the length of the inactive state periods while holding the length of the active state periods constant.

Abstract: A load control device may be configured to turn on lighting loads to obtain a fast turn-on time that may be substantially consistent across lighting loads that have different load voltages. The load control device may comprise a power converter circuit configured to produce a voltage across a capacitor, and a control circuit configured to control the power converter circuit to generate the voltage across the capacitor. The control circuit may determine a learned voltage from the magnitude of the voltage across the capacitor. For example, the control circuit may measure the magnitude of the voltage and store the measured voltage as the learned voltage. The control circuit may determine an operating parameter for the power converter circuit as a function of the learned voltage, and control the power converter circuit according to the operating parameter to charge the capacitor until the magnitude of the voltage exceeds a threshold.

Abstract: An illumination device and method is provided herein for calibrating individual LEDs and photodetector(s) included within the illumination device, so as to obtain a desired luminous flux and a desired chromaticity of the device over time as the LEDs age. Specifically, a calibration method is provided herein for characterizing each emission LED and each photodetector separately. The wavelength and intensity of the illumination produced by each emission LED is accurately characterized over a plurality of different drive currents and ambient temperatures, and at least a subset of the wavelength and intensity measurement values are stored with a storage medium of the illumination device for each emission LED. The responsivity of the photodetector is accurately characterized over emitter wavelength and photodetector junction temperature, and results of said characterization are stored with the storage medium.