Abstract: A system may include a set of light-emitting diode (LED) circuits, wherein each LED circuit of the set of LED circuits comprises: a first electrode; a set of second electrodes; and a set of pixels, wherein each pixel of the set of pixels corresponds to a combination of the first electrode and a respective second electrode of the set of second electrodes. A plurality of pixels may include the set of pixels corresponding to each LED circuit of the set of LED circuits. The first electrode may be located within a center portion of the respective LED circuit, and each second electrode of the set of second electrodes may be located within an outer portion the respective LED circuit. The system also includes a controller circuit configured to control whether each pixel of the plurality of pixels is activated or deactivated.

Abstract: A TEG near the perimeter of a frame region is away from a TFT, which is disposed in a display region and is actually used for screen display. Hence, the characteristics of the TEG can change in a manner different from that in the characteristics of the TFT within the display region. Accordingly, provided is a display device that includes a TEG pattern disposed between the display region and a trench, and includes a dummy pixel circuit disposed between the display region and a barrier wall. The TEG pattern is outside the display region and is adjacent to at least the dummy pixel circuit.

Abstract: A light emitting display device comprises a subpixel having a light emitting element disposed in a light emission area on a substrate and a circuit area in which a circuit for driving the light emitting element is disposed, a gate line disposed in the circuit area in a first direction, and at least one power line disposed in a second direction crossing the first direction, the at least one power line including a first power bridge line and a second power bridge line which are spaced apart from each other in the first direction.

Abstract: The present disclosure provides an electrostatic protection circuit for display panels, a method, a display panel, and a display device. The display panel includes an array substrate, a chip on film (COF) substrate connected to the array substrate, and at least a remaining testing line. The electrostatic protection circuit includes at least a first electrostatic protection line configured to connect at least the remaining testing line to a grounding line of the COF substrate.

Abstract: A display device includes a first display area including a plurality of first pixel areas and a second display area including a plurality of second pixel areas and a plurality of light transmitting areas. Each of the plurality of first pixel areas includes at least one first pixel to display an image. Each of the plurality of second pixel areas includes at least one second pixel to display the image. The light transmitting area does not include a pixel capable of displaying the image and has higher light transmittance than the second pixel area. In the second display area, at least one of the plurality of light transmitting areas is between two second pixel areas adjacent in a first direction, and at least one of the plurality of light transmitting areas is between two second pixel areas adjacent in a second direction different from the first direction.

Abstract: The present disclosure relates to a pixel circuit and a display device using the same. The pixel circuit includes a first switch element configured to connect a first node to a third node in a sampling step, a second switch element configured to supply a data voltage to a second node in the sampling step, a third switch element configured to supply a pixel driving voltage to the second node in a emission step after the sampling step, a fourth switch element configured to connect the third node to an anode of a light-emitting element in the emission step, a first capacitor connected to the first node, a second capacitor connected between the third node and the anode of the light-emitting element, and a third capacitor connected between the anode and the cathode of the light-emitting element.

Abstract: An electronic device including a housing, a display panel with a flexible substrate, and a flexible printed circuit, in which the housing comprises a flat surface and a side surface comprising a curved region, the display panel comprises a first region that overlaps with the flat surface and a second region that overlaps with the side surface, the display panel comprises a convex portion that comprises a region overlapping with a flexible printed circuit, and the display panel comprises a display portion in the first region and the second region.

Abstract: A pixel circuit includes a data written-in sub-circuit, a driving sub-circuit, a threshold compensation sub-circuit, a light-emitting element, a sensing sub-circuit and a first light-emission control sub-circuit. The driving sub-circuit is configured to control a driving current for driving the light-emitting element to emit light. The data written-in sub-circuit writes threshold compensation information into a second terminal of the driving sub-circuit at a compensation stage. The threshold compensation sub-circuit stores a data signal and adjusts a voltage at the second terminal of the driving sub-circuit in a coupled manner. The sensing sub-circuit writes a sensing voltage into a first terminal and the second terminal of the driving sub-circuit at a display process, senses aging information of the light-emitting element during an aging detection process and transmits the aging information to the aging detection device.

Abstract: A method includes performing by a processor: estimating a total cathode space current for a thermionic vacuum tube having at least one grid and a plate, such that at least one amplification factor associated with the at least one grid is determined by a polynomial based on a variable that represents at plurality of voltages associated with the at least one grid and the plate, the variable being heuristically determine. Transitions between positive and negative grid operation may experience a step change in estimated current value caused by the inclusion or elimination of grid current. A part of the grid current may be added back into the plate current during transition. This small contribution to plate current may gradually diminish as tube operation moves farther away from the transition boundary.

Abstract: A projection system, a beam generating apparatus, and a beam generating method are provided. The beam generating apparatus includes a plurality of light emitting devices, a plurality of drivers, and a first auxiliary driver. The light emitting devices respectively generate a plurality of color lights with different wavelengths. The drivers respectively drive the light emitting devices according to a plurality of control signals. The first auxiliary driver drives a first light emitting device according to a first auxiliary control signal, and adjusts brightness of the first light emitting device according to a first regulating signal. When the first auxiliary control signal is enabled, the control signal corresponding the first light emitting device is disabled.

Abstract: The present disclosure provides a backlight module and a display device, and relates to the field of display technology. The backlight module includes a light guide plate, a light source, a frame portion adjacent to a light incident surface of the light guide plate, and one or more positioning members for defining a position of the light source. The at least one positioning member includes a first positioning portion and a second positioning portion. The first positioning portion is located on a surface of the frame portion adjacent to the light incident surface. The second positioning portion is located on the light incident surface. The second positioning portion and the first positioning portion are mutually constrained to restrict relative movement of the light guide plate and the frame portion in a length direction of the light incident surface.

Abstract: A display may include an array of organic light-emitting diode display pixels having transistors characterized by threshold voltages subject to transistor variations. Compensation circuitry may be used to sense a current from selected display pixels. A display pixel may include a drive transistor, a gate setting transistor for driving a reference voltage onto the gate terminal of the drive transistor, a data loading and current sensing transistor for connecting the drive transistor to a data/current-sensing line, a light-emitting diode, an emission control transistor coupled between the drive transistor and the diode, and an anode resetting transistor for selectively resetting the anode terminal of the diode. During pixel conditioning and current sensing operations, the anode resetting transistor may be constantly turned on to ensure that there is no voltage perturbation at the source terminal of the drive transistor, which can help prevent hysteresis-induced current sensing error.

Abstract: An intelligent lighting system may be installed using pre-existing electrical wiring, such as in a construction or retrofit environment. An intelligent lighting controller and an intelligent lighting fixture may be connected via electrical wiring that is configured for transmitting AC power signals. A commissioning signal may be transmitted to the intelligent lighting fixtures via the electrical wiring. In some cases, the intelligent lighting controller modifies portions of the AC power signal to indicate the commissioning signal. The intelligent lighting fixtures may receive the commissioning signal via the electrical wiring. In some cases, each intelligent lighting fixture that is connected to the electrical wiring, such as each intelligent lighting fixture on a lighting circuit in a room, receives the commissioning signal.

Abstract: An energy storage system is presented. The energy storage system includes a primary energy storage device operatively couplable to a main bus, where the main bus is operatively coupled to a power generation device. Further, the energy storage system includes an auxiliary bus operatively couplable to the main bus and a grid bus. Furthermore, the energy storage system includes a plurality of auxiliary loads operatively coupled to the auxiliary bus and a housing configured to encompass the primary energy storage device, the auxiliary bus, and the plurality of auxiliary loads, where the auxiliary bus is configured to supply power to the plurality of auxiliary loads from the primary energy storage device, the power generation device, a grid, or combinations thereof.

Abstract: A method and apparatus filter light spectrum. Ambient light conditions of light that is ambient to a user device can be sensed. Ambient light color conditions can be determined based on the sensed ambient light conditions. User device charging times when the user device is being charged can be monitored. User device motion including movement of the user device can be monitored. User device activity can be monitored. Color-modified image display times can be ascertained from at least one selected from the user device motion, the user device activity, and the user device charging times. A color-modified image can be generated based on at least the ambient light color conditions and the color-modified image display times. The color-modified image can be displayed.

Abstract: An electrical characteristics inspection method is provided. A pixel compensation circuit of a display panel comprises a plurality of thin film transistors. The method comprises steps of: removing a film layer above a drain electrode of the thin film transistor; cutting the connection between the thin film transistor and the other thin film transistors in the pixel compensation circuit using a first laser, cutting the connection between the thin film transistor and the other pixel circuits using the first laser; inserting a probe into a probing location, and supplying a predetermined voltage to the probe for measuring the electrical characteristics of the thin film transistor. This method allows the probe to more precisely touch the metal layer in the display area. It can test and analyze the electrical characteristics in the dense display area more easily. And further can avoid the electrical effects from other thin film transistors.

Abstract: An AMOLED display panel includes data lines, scanning lines, a plurality of pixel units surrounded by the data lines and the scanning lines, a plurality of first driving circuits correspondingly arranged in pixel units arranged on predetermined positions, a plurality of second driving circuits arranged in the pixel units on another positions, and a temperature adjustment circuit. An input terminal of the temperature adjustment circuit is connected to the first pixel driving circuits, and an output terminal of the temperature adjustment circuit is connected to the data lines.

Abstract: The present application provides an AMOLED pixel driving circuit and a driving method thereof. The AMOLED pixel driving circuit employs a 6T1C pixel driving circuit with a specific driving timing to effectively compensate the threshold voltage to drive the thin film transistors and stabilize the current flowing through the OLED, to ensure uniform luminance of organic light emitting diodes and improve the display effect of the image. Meanwhile, the combination of the N-type thin film transistor and the P-type thin film transistor to reduce the number of the thin film transistors and the scan control signals to simplify the structure of the pixel driving circuit and increase the luminous area.

Abstract: A pixel circuit, a display panel and a driving method are described. The pixel circuit includes: a light-emitting circuit configured for emitting light during a working period; a driving circuit configured for driving the light-emitting circuit; a compensating circuit configured for compensating the driving circuit; a data writing circuit configured for writing data to the driving circuit; a reset circuit configured for resetting the compensating circuit and the driving circuit; a first light-emitting control circuit configured for controlling ON and OFF of the light-emitting circuit.

Abstract: The present invention provides an organic light emitting diode (OLED) display array substrate, a manufacturing method of the same OLED structure and a display apparatus. The OLED array substrate includes a plurality of pixels arranged in an array on a base substrate. Further, each pixel comprises a first sub-pixel and a second sub-pixel displaying different colors. Each sub-pixel comprises a light emitting unit and a control circuit. In addition, an orthogonal projection of the light emitting unit of the first sub-pixel on the base substrate overlaps with an orthogonal projection of the control circuit of the second sub-pixel on the base substrate. According to the OLED display structure of the present disclosure, the region occupied by the control circuit of a second sub-pixel is used to set up the light emitting unit of the first sub-pixel. This can increase the display surface area occupied by the light emitting units in each pixel, thus improve the resolution of the display.

Abstract: An organic light emitting display device includes pixel driving circuits to control pixels which include organic light emitting diodes. The pixel driving circuits include a first pixel driving circuit and a second pixel driving circuit, and the organic light emitting diodes include a first organic light emitting diode. The first organic light emitting diode emits light at a first brightness based on a driving current from the first pixel driving circuit in a first frame, and emits light at a second brightness based on a driving current from the second pixel driving circuit in a second frame.

Abstract: An LED driver chip for a car reading light and a state control method thereof are provided. The LED driver chip includes a state machine control circuit module, a state machine output logic module, a current on/off control logic circuit module, and a current source module. An OUT pin of the LED driver chip is connected with an LED. The LED driver chip determines the next state of LED current according to a driver chip PWM input signal, an EN pin low lever pulse input signal, and a present LED state, enabling the LED to switch among nine different states.

Abstract: An LED module includes, on a circuit board, first to fourth electrodes, a first circuit including a first LED group, and a second circuit including second and third LED groups, a switch element and a detection element. The second circuit includes a first path leading from the second LED group to one end of the detection element, and a second path leading from the third LED group via the switch element to one end of the detection element. The first and second electrodes are connected to the first circuit, the third electrode is connected to the second and third LED groups, and the fourth electrode is connected to the other end of the detection element. The threshold voltage for light emission of the second LED group is larger than that of the third LED group. The switch element controls a current flowing through the second path in accordance with a current flowing via the detection element.

Abstract: A system for driving a display that includes a plurality of pixel circuits arranged in an array, each of the pixel circuits including a light emitting device and a driving transistor for conveying a driving current through the light emitting device. Methods of measuring characteristics of circuit elements of pixels sharing a monitor line include the control of biasing to selectively turn off circuit elements or render their response known while measuring other circuit elements of interest.

Abstract: A twinkling door hanger mainly includes a main decoration, secondary decoration, illumination device and hanging portion. The secondary decoration is configured on the top of the main decoration, being different from the main decoration in material; the illumination device has at least one illumination element configured inside the main decoration; the hanging portion is configured above the main decoration, capable of being hung on a door knob, allowing the present invention to achieve a decoration profiting effect through the configuration of the illumination element.

Abstract: A transparent organic light-emitting display device is described herein. The transparent substrate includes a display area and non-display area adjacent to the display area. An organic light-emitting element is disposed on the display area of the transparent substrate. A first power line is disposed on the display area of the transparent substrate. The first power line supplies power to the organic light-emitting element. A first circuit board comprises a first power supply provided on a first side of the transparent substrate and a second circuit board comprises a second power supply provided on a second side of the transparent substrate. The first power supply is configured to receive power from the second power supply via the first power line. An additional interconnection film to supply power to the first power supply is not required, and thus the width of the bezel can be reduced.

Abstract: Controllers (360, 360?), lighting circuits and methods are disclosed, for a dimmable LED lighting circuit having a series arrangement of two types of LED, the controller comprising a control circuit (330), a bypass circuit (340) and optionally a further bypass circuit and being operable for controlling a current, the current (Idriver) being separable into first and second parts (IW, IB), and into further first and second parts, wherein the controller is configured to direct the (further) first part through the LED or LEDs of the second (first) type and direct the (further) second part through the (further) bypass circuit (respectively), and wherein the control circuit is configured to adjust the ratio between the first, or further first, part and the second, or further second respectively, part in dependence on a dimming level of the LED lighting circuit.

Abstract: Disclosed is a light emitting device including a light emitting structure including a plurality of light emitting regions comprising a first semiconductor layer, an active layer and a second semiconductor layer, a first distributed bragg reflective layer disposed on the light emitting regions, a first electrode unit disposed on the first semiconductor layer in one of the light emitting regions, a second electrode unit disposed on the second semiconductor layer in another of the light emitting regions, an intermediate pad disposed on the first semiconductor layer or the second semiconductor layer in at least still another of the light emitting regions, and at least one connection electrode disposed on the first distributed bragg reflective layer such that the connection electrode sequentially connects the light emitting regions in series.

Abstract: Disclosed is a light emitting device including a light emitting structure including a plurality of light emitting regions including a first semiconductor layer, an active layer and a second semiconductor layer, and a plurality of boundary regions disposed between the light emitting regions, a first electrode unit disposed on the first semiconductor layer in one of the light emitting regions, a second electrode unit disposed on the second semiconductor layer in another of the light emitting regions, at least one connection electrode to electrically connect the first semiconductor layer of one of adjacent light emitting regions to the second semiconductor layer of the other thereof, and an intermediate pad disposed on the first semiconductor layer or the second semiconductor layer in at least one of the light emitting regions, wherein the light emitting regions are connected in series through the connection electrode.

Abstract: An organic light emitting display device includes a pixel unit, a first voltage supply unit, a second voltage supply unit, and a selection unit. The pixel unit includes a plurality of pixels coupled to power lines. The first voltage supply unit is configured to output a first voltage. The second voltage supply unit is configured to output a second voltage. The selection unit is configured to supply any one of the first and second voltages to the pixels through the power lines.

Abstract: A lighting device includes: a plurality of DC power supply circuits. A plurality of light sources and switching units are connected to each of the DC power supply circuits, the switching units being configured to respectively switch electrical connection between the light sources and said each of the DC power supply circuits. A difference in rated voltage between any two light sources connected to one of the plurality of DC power supply circuits in common is smaller than a difference in rated voltage between two light sources respectively connected to different DC power supply circuits of the plurality of DC power supply circuits.

Abstract: The present invention discloses a power circuit having multiple stages of charge pumps. The power circuit comprises a first charge pump, a second charge pump, a voltage stabilizing capacitor, and an output capacitor. The first charge pump adjusts an input voltage and produces a first output voltage. The second charge pump adjusts the first output voltage, produces a second output voltage, and outputs the second output voltage for driving a loading. The voltage stabilizing capacitor is coupled between the first and second charge pumps and connected externally to the output of the first charge pump. The output capacitor is coupled to the second charge pump for providing the second output voltage. According to the present invention, the effect of supplying large transient currents to the loading can be achieved by connecting externally the voltage stabilizing capacitor to the output of the first charge pump.

Abstract: There is provided an apparatus for driving a light emitting diode (LED), capable of distributing current stress applied to the LED. The apparatus includes an LED part including a plurality of LED units respectively including at least one LED, the plurality of LED units being connected in parallel to a power input terminal to which rectified power in sine wave form is supplied, and, among the plurality of LED units connected in parallel, a termination end of the LED unit in a front end being connected to a middle of an adjacent LED unit; and a current source unit including a plurality of current sources respectively connected to termination ends of the plurality of LED units and allowing corresponding current to flow through the plurality of LED units.

Abstract: In various embodiments, lighting systems include an electrically insulating carrier having a plurality of conductive elements disposed thereon, a light-emitting array, and at least one power source. The light-emitting array is disposed over the carrier and includes a plurality of light-emitting strings, each light-emitting string comprising a plurality of electrically connected light-emitting diodes (LEDs). Each LED has at least two electrical contacts, and each electrical contact is electrically connected to a conductive element by a conductive adhesive and/or a solder. The power source provides power to the light-emitting strings.

Abstract: The present invention relates to a gate driving circuit, and a array substrate and a display using the same.

Abstract: A converter circuit arrangement is provided, including a converter switch controller, a converter switch, a load circuit interface and an inductor. The converter switch controller may include a control input. The converter switch may be coupled between a first power supply potential and the control input. The inductor may be coupled between a second power supply potential and the load circuit interface. The load circuit interface may be coupled between the control input and the inductor.

Abstract: A dual-pixel circuit includes first and second OLEDs, and a driving circuit that includes first and second driving transistors, a capacitor, and a switching module operable between first and second modes based on a data voltage, first and second scan voltages, and first and second bias signals. When the switching module is operated in the first mode, the first OLED is forward-biased to emit light, and the second OLED is reverse-biased. When the switching module is operated in the second mode, the first OLED is reverse-biased, and the second OLED is forward-biased to emit light.

Abstract: A DC-DC converter includes a voltage conversion circuit unit, a control unit, and a capacitor check unit. The voltage conversion circuit unit converts an input voltage to a first voltage. The control unit controls the voltage conversion circuit unit based on a feedback voltage and a reference voltage. The capacitor check unit determines whether a capacitor is coupled to a capacitor coupling terminal based on sensing a voltage of the capacitor coupling terminal, which is selectively coupled to the first control unit.

Abstract: The present invention discloses a power circuit having multiple stages of charge pumps. The power circuit comprises a first charge pump, a second charge pump, a voltage stabilizing capacitor, and an output capacitor. The first charge pump adjusts an input voltage and produces a first output voltage. The second charge pump adjusts the first output voltage, produces a second output voltage, and outputs the second output voltage for driving a loading. The voltage stabilizing capacitor is coupled between the first and second charge pumps and connected externally to the output of the first charge pump. The output capacitor is coupled to the second charge pump for providing the second output voltage. According to the present invention, the effect of supplying large transient currents to the loading can be achieved by connecting externally the voltage stabilizing capacitor to the output of the first charge pump.

Abstract: A suppressor grid is configured proximate to an anode to produce a suppressor electric field selected to provide a force on an electron in a direction pointing away from the anode, wherein the suppressor electric field is further selected to pass electrons from the suppressor grid to the anode.

Abstract: Embodiments of the present invention are directed to a touch or close proximity activated low energy illumination apparatus. The illumination apparatus are configured to be positioned within personal portable carrying units such as purses, handbags, backpack, shoulder bags, computer bags, bags for communication devices or other container. The illumination apparatus is configured to illuminate inner compartments of such personal portable carrying units. In preferred embodiments, the apparatus is removably attachable to a personal portable carrying unit and can be oriented for the illumination of external objects such as a door lock of a car or building, or the immediate vicinity of a dark space. Certain embodiments may be affixed to or integrated into a personal portable carrying unit. Embodiments of the present invention may comprise a circuit assembly, a power source, at least one semiconductor illuminating device such as a light emitting diode and a plain or decorative pocket.

Abstract: Illumination devices and related systems and methods are disclosed that can be used for LCD (Liquid Crystal Display) backlights, LED lamps, or other applications. The illumination devices can include a photo detector, such as a photodiode or an LED or other light detecting device, and one or more LEDs of different colors. A related method can be implemented using these illumination devices to maintain precise color produced by the blended emissions from such LEDs. One application for the illumination devices is backlighting for FSC (Field Sequential Color) LCDs (Liquid Crystal Displays). FSC LCDs temporally mix the colors in an image by sequentially loading the red, green, and blue pixel data of an image in the panel and flashing the different colors of an RGB backlight. Precise and uniform color temperature across such a display can be advantageously maintained by continually monitoring ratios of photodiode currents induced by the different colored LEDs in each illumination device as each color is flashed.

Abstract: A lighting control module provides an enclosure for a circuit board, with the circuit board being mounted to and grounded to the enclosure. A primary power system is provided to receive and transmit voltage to lighting circuits, utilizing a terminal bus bar, a main switch, a voltage selection switch, and a transformer. An auxiliary power system draws energy from portable power sources in the event of a main power source failure. The auxiliary power system includes an associated terminal bus bar and an auxiliary switch. The primary and auxiliary power systems are connected to the lighting circuits through a circuit protection unit, e.g. fuse. The lighting circuits have both positive and negative terminals, LED indicators, switches, and individual fuses. The lighting circuits can be turned on and off individually by virtue of the switches for each lighting circuit. Status indicators and ground terminals are also provided.

Abstract: A LED lighting apparatus for growing plants includes a remote controlling device for sending wireless signals; and at least one lighting device each including a receiver and transmitter for receiving the wireless signals sent from the remote controlling device, a first power source electrically connected to the receiver and transmitter and being capable of supplying electricity to four downstream first LED groups connected in series, and a second power source electrically connected to the first power source via the first LED groups and being capable of supplying electricity to four downstream second LED groups connected in series.

Abstract: In one embodiment, the trajectory of one or more electrons is controlled in a field emission device. In another embodiment, the field emission device is configured analogously to a klystron. In another embodiment, the field emission device is configured with electrical circuitry selected to control the input and output of the device.

Abstract: It would be beneficial for engineers when renewing municipal infrastructure to have the option of centralizing multiple services into one physical element of infrastructure. It would also be beneficial where one specific element of infrastructure may be replaced to address replacement or operating costs, e.g. when replacing high pressure sodium, xenon, metal-halide, or mercury lighting with solid state lighting, that the new infrastructure supports migration to an overall reduction in physical infrastructure as other services/infrastructure elements are renewed. It would be further beneficial for the deployed physical element of infrastructure minimize physical footprint, offer low cost design solutions, improve reliability, support evolving requirements, offer new services and revenue-generating opportunities, enhance the payback and return on investment, as well the evolving needs of emergency services, security organizations, etc.

Abstract: A plurality of battery cells (100) are connected in series to each other. A temperature measurement unit (300) measures temperatures of two or more battery cells (100). A battery control unit (400) controls charge and discharge of the battery cells (100) on the basis of the temperatures measured by the temperature measurement unit (300). In addition, when the charge of the battery cells (100) is performed or the discharge of the battery cells (100) is performed, the battery control unit (400) specifies a lowest temperature cell having the lowest temperature and a highest temperature cell having the highest temperature, on the basis of the temperatures measured by the temperature measurement unit (300). In addition, the battery control unit (400) continues the charge or discharge, as it is, when a first condition in which a temperature difference ?T between the highest temperature cell and the lowest temperature cell is equal to or greater than a reference value T1 is not satisfied.

Abstract: LED lighting device and LED control system are provided. An LED lighting device includes an LED power supply unit, a controller unit, a microphone module, a wireless communication module, and an LED light source assembly. An LED control system includes at least one LED lighting device, at least one of a smart terminal and a cloud server, and at least one smart home appliance. When a user sends a voice command to the LED lighting device, the LED lighting device captures and processes signal data from the voice command to provide control data to the smart terminal or cloud server, which then recognizes and processes the control data to provide processed control data. The processed control data are then sent to a corresponding smart home appliance communicated with the smart terminal or the cloud server to control an operation of the smart home appliance.

Abstract: An LED lighting device includes multiple driving stages. A first driving stage includes a first luminescent device driven by a first current and a first current controller coupled in parallel with the first luminescent device. The first current controller is configured to conduct a second current according to a voltage established across the first current controller and regulate the second current so that a sum of the first current and the second current does not exceed a first value. The second driving stage includes a second luminescent device driven by a third current and a second current controller coupled in series to the second luminescent device. The second current controller is configured to conduct a fourth current according to a voltage established across the second current controller and regulate the fourth current so that a sum of the third current and the fourth current does not exceed a second value.

Abstract: A power converter circuit includes: a first transistor being connected with a positive node and a negative node of a photovoltaic panel; a second transistor being connected with the first transistor and the negative node of the photovoltaic panel; a first controller circuit being configured to measure the voltage at a reference node and adjust the gate voltage of the first and second transistors respectively; a third transistor being connected with the reference node and an output node; and a second controller circuit being configured to control the gate voltage of the third transistor. The reference node is connected to the second transistor through a LC network. The first controller circuit is configured to turn off the first and second transistors when the voltage at the reference node exceeds a threshold. The second controller circuit is configured to prevent current from being fed back through the LC network.