Abstract: A display control method for an ultra high definition television and a 8K ultra high definition television. Said Method comprises: receiving an inputted ultra high definition video signal, and converting the video signal into an RGB signal corresponding to a target resolution (S1); and driving, according to the target resolution corresponding to the RGB signal, a Micro LED display screen to display (S2). When the inputted video signal is a 8K ultra high definition signal, the 8K video signal is converted into an RGB signal, then the RGB signal is transmitted to a drive chip of the Micro LED display screen, and the drive chip lights up the whole Micro LED display screen according to the RGB signal, thereby achieving the display of the ultra high definition television.

Abstract: An integrated circuit for a power supply circuit that includes a transformer including a primary coil, a secondary coil, and an auxiliary coil, and a transistor controlling a current flowing through the primary coil. The integrated circuit includes a first determination circuit determining a state of the load; a second determination circuit determining whether a current of the secondary coil is in a continuous mode and a discontinuous mode, in which the current of the secondary coil respectively does not reach, and reaches, zero when the transistor is off; an oscillator circuit outputting an oscillator signal; and a switching control circuit controlling switching of the transistor in response to a determination result of the second determination circuit and the oscillator signal, and in response to the oscillator signal irrespective of the determination result of the second determination circuit, respectively when the state of the load is light and heavy.

Abstract: An instrument head for attachment to a plurality of instrument handles having different power sources is described. The instrument head includes at least one light-emitting diode, and a controller. When the controller detects an instability in a voltage input from a power source in an instrument handle attached to the instrument head, the controller transitions from a normal mode of operation to a mitigation mode of operation. The mitigation mode of operation prevents an increase in output of the at least one light-emitting diode for a predetermined period of time.

Abstract: A light source module is switchable between a high beam and a low beam, and is mounted on a vehicle. A first light source is arranged such that its output light is irradiated to a low-beam region by a first optical system. A second light source is arranged such that its output light is irradiated to a high-beam region by a second optical system. A lighting circuit supplies a driving current to the first light source in response to a turn-on instruction for either the high beam or the low beam. Furthermore, the lighting circuit supplies the output current to the second light source in response to a turn-on instruction for the high beam.

Abstract: A lighting control method includes: receiving light-emitting color data, the light-emitting color data including color values corresponding to a plurality of preset light-emitting channels; determining at least one additional light-emitting channel other than the plurality of preset light-emitting channels among the actual light-emitting channels of a lighting device; generating a color value of the additional light-emitting channel according to color values of the plurality of preset light-emitting channels in the light-emitting color data, and using the color values corresponding to the plurality of preset light-emitting channels and the additional light-emitting channel as target light-emitting color data; and transmitting the target light-emitting color data to each lamp bead chip in the lighting device to control corresponding lamp beads to emit light according to the color values corresponding to the actual light-emitting channel to which the lamp beads belong.

Abstract: Daisy-chained connected light emitting diode (LED) devices for an automotive direct backlight system are presented herein. Such system can include a group of LED devices communicatively coupled with respective LED devices of the group of LED devices in a daisy-chained manner via serial communication interfaces between the respective LED devices. A host device of the system is directly connected, via a serial peripheral interface, to a foremost device of the respective LED devices, and is communicatively coupled, via the foremost device, to successive devices of the respective LED devices in the daisy-chained manner. The host device synchronizes generation of light by the respective LED devices based on defined timing information, and sends, via the foremost device, respective optical and electrical characteristic data to each of the LED devices to facilitate modification, via LED drivers of the LED devices, of operating characteristics of respective LED chips of the LED devices.

Abstract: A driving circuit, a driving method and a display apparatus are provided. The driving method is provided for driving a light-emitting unit including a first light-emitting element series and a second light-emitting element series connected in parallel and connected to a processing unit and a driving unit of a driving circuit. The processing unit detects a first voltage value and a second voltage value. The driving unit detects and transmits a first current value and a second current value to the processing unit. The processing unit determines and compares a first power value and a second power value. When the first and second power values are different, the processing unit controls the driving unit to adjust a driving current setting of the light-emitting element series until the first and second power values are equal. The invention ensures luminance consistency of different light-emitting element series and the luminance uniformity of display apparatus.

Abstract: A control system for an LED array relies on defining a first and a second group of separately addressed LED pixels, with the first group including pixels with an average current no less than the current at a Q point and a second group including pixels with an average current less than the current at a Q point. An amplitude signal provided to the first group of separately addressed LED pixels is selectively modulated, while providing a DC mode 100% duty cycle. An amplitude signal provided to the second group of separately addressed LED pixels is fixed, and a modulated duty cycle is provided.

Abstract: A driving method includes, at a first display brightness value, inputting a pulse-width modulation signal with a duty ratio of X, and controlling a light-emitting driving current of a sub-pixel unit to be M, wherein X and M are obtained according to a first modulation rule; and at a second display brightness value, inputting the pulse-width modulation signal with a duty ratio of Y1, and controlling the light-emitting driving current of the sub-pixel unit to be N1, wherein the first display brightness value is greater than the second one, wherein, when the duty ratio and the light-emitting driving current corresponding to the second display brightness value are obtained according to the first modulation rule, the duty ratio corresponding to the second display brightness value is Y2, the light-emitting driving current corresponding to the second display brightness value is N2, Y1 is smaller than Y2, and N1 is greater than N2.

Abstract: A lighting arrangement such as a LED lamp comprises a light source and associated current driver, or a set of at least two parallel light sources and associated current drivers, supplied by a DC voltage from a voltage-regulated power converter. A feedback circuit provides a temperature-dependent control input to a control loop of the power converter, such that the DC voltage is adjusted in dependence on a sensed temperature. In this way, the voltage headroom required can be reduced, and efficiency gains are made.

Abstract: A backlight unit includes a substrate, a plurality of light source assemblies disposed on the substrate, each of the light source assemblies including first to k-th light sources, where the k is a natural number greater than or equal to two, a plurality of sensing lines disposed on the substrate, the sensing lines respectively connected to the first light sources of the light source assemblies, a connection line disposed on the substrate, the connection line connecting the first to k-th light sources of each of the light source assemblies in series, and a controller connected to the sensing lines, and a width of the connection line is greater than a width of each of the sensing lines.

Abstract: A lighting circuit turns on a plurality of semiconductor light sources. Multiple current sources are each coupled to a corresponding semiconductor light source. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits each formed of the semiconductor light source and the current source. A converter controller employing a ripple control method turns on a switching transistor of the switching converter in response to a voltage across any one of the multiple current sources decreasing to a bottom limit voltage.

Abstract: A light-emitting diode is disclosed, which includes: a substrate; a light-emitting diode chip disposed on the substrate; and a quantum dot film disposed on the light-emitting diode chip, wherein the quantum dot film includes a plurality of quantum dots and a matrix material, and a plurality of particles are dispersed in the matrix material, wherein the plurality of particles are conductive particles, semiconductor particles, or a combination thereof.

Abstract: An LED lighting apparatus, including an LED light source configured to emit white light having a first melanopic/photopic (M/P) ratio; a tuning LED light source configured to emit tuning blue light having a peak wavelength in a range of 465 nm to 495 nm; and a driving control unit configured to control currents respectively applied to the LED light source and the tuning LED light source to generate tuned white light having a second M/P ratio higher than the first M/P ratio

Abstract: To promptly detect a failure of a light source. A vehicle headlight system includes a plurality of light sources, a power supply supplying a drive voltage to the light sources, a controller individually controlling a lit/off state of each light source, and a failure detection circuit connected to the controller and detects a failure of the light sources, where, in response to a start of the vehicle, the controller executes a control operation in which all light sources are controlled from the off state to the lit state and then the light sources are controlled to the off state sequentially and individually, and where, while the control operation is executed, at least during the period of transition from the off state to the lit state of each light source, the controller acquires failure detection result and generates a warning signal when the failure is detected.

Abstract: The present disclosure provides an LED driving circuit and an LED driving method, which may be applied to a switching power supply driving circuit and a linear driving circuit. The LED driving circuit includes an adjusting tube and a driving control circuit of the adjusting tube. The adjusting tube receives an input voltage, and the driving control circuit adjusts the adjusting tube to output an output current to be expected. A reference generating circuit samples an output voltage of the LED driving circuit to obtain an output voltage sampling signal and a reference current signal corresponding to the output voltage sampling signal. A current adjusting circuit samples the output current to obtain an output current sampling signal, receives the corresponding reference current signal, and controls a conduction state of the adjusting tube according to the output current sampling signal and the reference current signal.

Abstract: A platform for design of a lighting installation generally includes an automated search engine for retrieving and storing a plurality of lighting objects in a lighting object library and a lighting design environment providing a visual representation of a lighting space containing lighting space objects and lighting objects. The visual representation is based on properties of the lighting space objects and lighting objects obtained from the lighting object library. A plurality of aesthetic filters is configured to permit a designer in a design environment to adjust parameters of the plurality of lighting objects handled in the design environment to provide a desired collective lighting effect using the plurality of lighting objects.

Abstract: A control system for an LED array relies on defining a first and a second group of separately addressed LED pixels, with the first group including pixels with an average current no less than the current at a Q point and a second group including pixels with an average current less than the current at a Q point. An amplitude signal provided to the first group of separately addressed LED pixels is selectively modulated, while providing a DC mode 100% duty cycle. An amplitude signal provided to the second group of separately addressed LED pixels is fixed, and a modulated duty cycle is provided.

Abstract: An example apparatus is for use with an electronic circuit breaker having a plurality of current paths connected between a connection terminal to a power source and a load terminal. The apparatus includes power access circuitry and control circuitry. The power access circuitry monitors circuit access of power via the power source by modulating use of the plurality of current paths of the electronic circuit breaker while assessing actual usage of the power source via a power-related parameter relative to expected usage of the power source. The control circuitry responds to the assessment by generating a signal indicative of a diagnostic result associated with operation of the electronic circuit breaker.

Abstract: An assembly and a method is provided where the LED module includes a plurality of module units interconnected between common connection lines in a sequential order with increasing distances towards a connection terminal of the LED module. The circuit assembly includes an output terminal having a first output terminal portion and a second output terminal portion, a main power supply for supplying an operation voltage potential to a first output terminal portion, a control device for generating a pulse width modulation signal, and an electronic switch coupled to the control device and configured to obtain the pulse width modulation signal and arranged to connect and disconnect a second output terminal portion to/from a reference potential in accordance with the pulse width modulation signal, such as to supply a pulse width modulated voltage to the output terminal. A pulse shaping unit is coupled to the control device.

Abstract: The invention provides a retrofit LED lamp driver having a shunt switch to alternately shunt (for a first duration) and not shunt (for a second duration) received AC power. The first duration is concurring with a first polarity of each AC cycle of the AC power, for a first period comprising at least one AC cycle, and the first duration is concurring in a second, opposite polarity of the AC power, for a second period comprising another at least one AC cycle not overlapping with the first duration. Alternating the first and second periods are provided. Any DC offset in the current drawn caused by the shunting operation is thereby cancelled over time.

Abstract: A driver circuit that includes an input side including a power input circuit and an output side including a light emitting diode (LED) output current circuit. The output side of the driver circuit includes an output smoothing capacitor for controlling flicker percentage. A light emitting diode (LED) power supply circuit is present between the input side and the output side for controlling current from the AC power input circuit to the light emitting diode (LED) output current circuit. The LED power supply circuit includes at least two linear current regulators that are connected in parallel. The circuit also includes a controller circuit including a controller for signaling the light emitting diode (LED) power supply to control current to the light emitting diode (LED) output current circuit to provide a lighting characteristic.

Abstract: An LED lighting apparatus includes a first LED light source and a second LED light source included in a first light source group; a third LED light source and a fourth LED light source included in a second light source group; a mode detection circuit configured to determine a mode; a current control unit for serial and parallel connection of the first light source group and the second light source group; balancing circuits for serial and parallel connection of the respective light source groups; and a current path providing circuit for providing current paths. The LED lighting apparatus performs light emission in various states depending on the change of a rectified voltage and the change of a mode.

Abstract: The invention discloses a device for detecting load state of driving power supply, the present invention can detect the load state of the driving power supply by using the parasitic capacitance, the pull-down resistor module inside the main control unit and the level detecting module in the circuit, without adding peripheral circuit. In this way, the actual product volume of the present invention does not increase, nor does it need to increase the hardware cost.

Abstract: A fault detector circuit is provided for detecting or controlling any signal related to a laser emitter in an electronic device. The fault detector circuit includes a first NMOS transistor and a comparator. A drain of the first NMOS transistor is coupled to a first supply voltage through the laser emitter. A gate of the first NMOS transistor is coupled to a control voltage. A source of the first NMOS transistor is grounded. The comparator is coupled to the drain of the first NMOS transistor and a reference voltage. The comparator compares a voltage of the drain of the first NMOS transistor with the reference voltage to generate a first detecting signal for determining whether or not the first supply voltage of the laser emitter needs to be cut off.

Abstract: A dimming circuit and a lighting device includes a signal processing unit having a first controllable switch connected to a to-be-processed dimming signal, a first port of a controller, and a first voltage signal; the to-be-processed dimming signal and the first voltage signal controlling turning-on/off the first controllable switch, the to-be-processed dimming signal being converted into a second voltage signal, and outputted from the second terminal to the controller; and the controller, extracting a corresponding dimming control signal based on change of the second voltage signal, and outputting the dimming control signal to a to-be-dimmed terminal. This circuit converts a electrical signal implements dimming control in conjunction with the controller, and the controller only processes weak electrical signals, thereby guaranteeing the reliability of the output voltage of the dimming circuit, and preventing the output voltage of the dimming circuit from harming the to-be-dimmed terminal.

Abstract: The present invention provides a lamp capable of preventing an increase in weight and dissipating heat of the LED module. The lamp of the present invention includes an LED module serving as a light source, a heat transfer unit, a light distribution unit, a casing including an opening, and a light transmissive cover. The LED module includes plural LEDs and an LED substrate having an LED-mounting surface on which the plural LEDs are mounted. The light distribution unit is disposed on a light emitting side of the LED module. The LED module and the light distribution unit are disposed in the casing. The light transmissive cover is disposed over the opening of the casing. The LED module is disposed in the casing to be distanced from the casing. The heat transfer unit is disposed such that heat of the LED module can be dissipated into the casing.

Abstract: The present disclosure relates to a pixel circuit including a light emitting unit, a processing circuit and a driving circuit. The processing circuit is configured to receive a frame display signal, and is configured to calculate the frame display signal to generate a driving duty cycle corresponding to a driving period according to a driving current value. The driving circuit is electrically connected to the processing circuit and the light emitting unit, and is configured to drive the light emitting unit during the driving period according to the driving duty cycle, the driving current value and a driving frequency.

Abstract: A system, a display, and a method. The display may include a backlight including a plurality of light emitting diodes (LEDs), the plurality of LEDs comprising a first group of LEDs and a second group of LEDs. The display may further include a processor communicatively coupled to the plurality of LEDs. The processor may be configured to: cause the first group of LEDs to pulse; and cause the second group of LEDs to pulse, wherein the first group of LEDs pulse out of phase from the second group of LEDs.

Abstract: A lighting device using multiple scattered light sources to change illumination angle and color temperature by adjusting light intensity includes a central light source portion, a peripheral light source portion and an optical lens on a lamp board. The optical lens covers the central and peripheral light source portions. The central light source portion has first cold LEDs and first warm LEDs equidistantly installed near a setting area of the lamp board. The peripheral light source portion has second cold LEDs and second warm LEDs installed within an area range that takes the setting center as center of circle and has a diameter of 6-8 mm. A controller is used to adjust a driving current intensity of the central and peripheral light source portion to adjust the illumination angle and color temperature of the lighting device, and the intensity performance or On/Off state of each LED can be controlled independently.

Abstract: Disclosed is an outdoor light fixture assembly having a housing, a contact block, and a user serviceable light module. The housing has a first opening for receiving the contact block and a second opening for receiving the user serviceable light module. The contact block has at least one contact and a power wire. The contact block can be disposed relative to the first opening so that the at least one contact is accessible from inside the housing. The user serviceable light module light module is sized and shaped to transition between a connected position and a released position relative to the housing. The user serviceable light module has a cover and a circuit board supporting one or more light emitting diodes and having at least one contact pin. The light emitting diodes are arranged relative to the circuit board to emit light in a direction towards the second opening when the user serviceable light module is in the connected position.

Abstract: An LED board comprises an arrangement of LEDs, a current sensor for sensing a current flowing through the arrangement of LEDs and a cut-off switch in series with the arrangement of LEDs. The cut-off switch is controlled in dependence on the sensed current. In this way, over-current protection is provided at the LED board level, without needing any signal communication between the LED board and the LED driver.

Abstract: A retrofit Light Emitting Diode, LED, lighting device for connection to a ballast, wherein said ballast is arranged to provide for a ballast current, said retrofit LED lighting device comprising at least one LED for emitting light, a rectifier arranged for rectifying said ballast current and for providing a lamp current to said at least one LED, a shunt switch for shunting said at least one LED thereby preventing said lamp current to flow through said at least one LED, a control unit for controlling said shunt switch, wherein said control unit is arranged to detect a particular amplitude offset current level in one of said ballast current and said lamp current, said particular amplitude offset current level being a particular non-zero value of said ballast current or said lamp current and to activate said shunt switch triggered by said detection.

Abstract: Disclosed is an LED display device and a method for driving the same. The LED display device comprises: an LED array comprising LEDs; a row driving module having output terminals, each of which is connected to a corresponding LED row for providing a supply voltage; constant current sources, each of which controls a driving current flowing through a corresponding LED column when a corresponding LED row is powered by the supply voltage; and voltage limiting modules, each of which is connected between a corresponding constant current source and a corresponding LED column. Current paths through a short-circuited LED and an open-circuited LED are disconnected by a corresponding voltage limiting module when there is a short-open failure in the LEDs. The LED display device can be used to improve image quality and reduce power consumption even if there is a short-open failure in the LEDs.

Abstract: An AC electric rolling stock controller includes a comparator that compares an intermediate link voltage VEFC generated at a smoothing capacitor with a setting value A, a comparator that compares the intermediate link voltage VEFC with a setting value B less than the setting value A, and a delayer that delays an output of the comparator in a case in which the output of the comparator is significant. It is determined that the initial charging of the smoothing capacitor is complete in a case in which at least one of an output of the comparator and an output of the delayer is significant.

Abstract: A method of sequencing an LED light string includes steps of: (a) using a control module to provide a pulse signal to an LED light string having a plurality of LED lights, (b) obtaining an LED light with a current sequence characteristic of the LED light string at a first rising edge or a first falling edge of the pulse signal, (c) self memorizing, by the LED light, as a current sequence, and changing a self state of the LED light so that the current sequence characteristic is no longer generated, and (d) repeating to perform step (b) and (c) at next rising edge or next falling edge of the pulse signal so as to obtain the sequence of the LED lights.

Abstract: A method includes mounting a light emitting device on a board having electrodes on its surface, disposing a resin sheet containing a light conversion material so as to face the surface of the board and filling a space between the resin sheet and the board with a first light transmissive resin, covering a surface of the resin sheet opposite to a surface of the resin sheet covered with the first light transmissive resin, with a second light transmissive resin, forming a groove extending from a top surface of the second light transmissive resin to the board, filling the groove with light reflective resin and covering the top surface of the second light transmissive resin with the light reflective resin, removing the light reflective resin, and dicing the light emitting device by cutting along the light reflective resin.

Abstract: A system and method involving lighting fixtures, a control network, a controller and other devices such as light sensors, input devices and network adapters for coordinating precise brightness and color schedules among the lighting fixtures while maintaining a high color reliability including provisions for managing a plurality of lighting fixtures. The lighting fixtures contain lighting elements selected such that when controlled properly, operating along a daytime locus, the resultant light output closely resembles sunlight on a cloudless day in spectral characteristics, and wherein the total flux of blue light can be adjusted from a relative level of 1-100% the maximum blue flux of the lighting fixture by controlling individual lighting elements.

Abstract: A resonant power converter (e.g., LED driver) comprises a switching power stage having an operating frequency to produce output current through an LED load. A current sensor is coupled to the LED load, and a negative control means regulates the operating frequency based on error signals from the sensed current relative to a reference value. A reference control circuit controls the error signal (e.g., by manipulating the reference value) responsive to the error signal exceeding a reference error signal for regaining negative feedback control. The reference control circuit includes a quick discharge circuit for quickly reducing the error signal when it exceeds the reference error signal, and a slow charge circuit for slowly increasing the error signal when it is reduced, for example giving the LED load time to warm up in transition from a cold operational state to a normal operational state.

Abstract: A circuit arrangement (1) for generating a reference voltage (Uref) for the power supply (2) of an LED arrangement (LED), wherein the power supply supplies a feed current (IS) to the LED arrangement on the basis of an input voltage (UB), which current is determined by the magnitude of the reference voltage, wherein the circuit arrangement comprises: a first voltage divider (R1/R2), located on a constant power supply voltage (UV), a second voltage divider (R3/R4), located on the input voltage (UB) of the power supply (2), and a third voltage divider (R5/R6) which consists of an ohmic resistor (R5) and a temperature-dependent resistor (R6) thermally coupled to the LED arrangement, a voltage proportional to the voltage on the centre connection of the second voltage divider (R3/R4) is supplied via a first diode (D1) to the centre connection of the first voltage divider (R1/R2), a voltage proportional to the voltage on the centre connection of the third voltage divider (R5/R6) is further supplied via a second diod

Abstract: A light source driving apparatus including a primary side and a secondary side is provided. The light source driving apparatus includes an isolated current sensing circuit, a dimming circuit, an independent voltage source, and a feedback circuit. The isolated current sensing circuit is coupled to the secondary side, and samples an output current of the light source driving apparatus by electromagnetic coupling to generate a current sensing signal. The dimming circuit receives a dimming input signal, and provides a reference controlled-current signal according to the dimming input signal and based on an operating voltage. The independent voltage source is configured to generate the operating voltage. Based on the operating voltage, the feedback circuit provides a feedback signal according to the current sensing signal and the reference controlled-current signal for adjusting the output current of the light source driving apparatus.

Abstract: A dimmer control circuit for controlling a phase cut dimmer includes: a rectifier circuitry, configured to rectify the output voltage of the phase cut dimmer to output a rectified voltage; an input voltage detecting circuitry, configured to output a detected voltage according to the rectified voltage; a processor, configured to output a control signal when the detected voltage meets a preset condition; and a constant current circuitry, configured to output or stop outputting a preset current to the rectifier circuitry in response to the control signal; wherein the preset current has a value greater than a holding current of the phase cut dimmer.

Abstract: To provide a method for lighting a backlight of a capacitive touch switch module in which driving of the backlight hardly affects sensitivity of a touch switch. An electrical noise generated when a LED backlight 6 is driven is suppressed by at least one of (1) setting timings of turning on and/or turning off of pulse waveforms for light emitting diode backlights in a pulse modulation system not to be the same but to be different from each other, and (2) lengthening a time necessary for at least one of rising and falling of the pulse waveform in the pulse modulation system.

Abstract: The present disclosure provides a multi-mode dimming control method and a dimming circuit. The multi-mode current control method includes: receiving a dimming signal, and controlling the dimming circuit to be operated in a plurality of modes in an arbitrary order according to the dimming signal, wherein the plurality of modes include any two or all of a first dimming mode, a second dimming mode, and a third dimming mode. Also, the dimming circuit can be operated in different combinations of different modes according to actual needs, so that the requirements of a wide dimming range and a low output current ripple can be realized.

Abstract: A solid state lighting SSL assembly comprises an SSL device, a capacitor, a directional conducting device and a supply switch. The capacitor is coupled in parallel with the SSL device. The directional conducting device is coupled between an output terminal of the capacitor and a supply terminal which provides a supply voltage for the SSL assembly. The directional conducting device is configured to conduct in a direction from the output terminal to the supply terminal and to isolate in the opposite direction. The supply switch is coupled between the output terminal and ground. In addition, a method for operating a solid state lighting SSL assembly is proposed.

Abstract: A light device driving system includes a voltage source managing module, a duty cycle adjusting module, a control integrated circuit, a power outputting module, a passive lighting device and a voltage/current output control module. The voltage source managing module generates an input voltage. The duty cycle adjusting module adjusts a duty cycle of a phase-width modulation signal of the light device driving system according to a voltage feedback signal. The control integrated circuit generates the phase-width modulation signal based on the adjusted duty cycle. The voltage/current output control module generates the voltage feedback signal according to the output voltage and a voltage dimming signal and configured to forward the voltage feedback signal to the duty cycle adjusting module.

Abstract: A voice recognition communication system may include a voice recognition server, a smart speaker device configured to communicate with the voice recognition server over a network, a power source, and a privacy interrupt device coupled between the smart speaker device and the power source. The privacy interrupt device may include a power switch configured to selectively toggle between a first state where the power source and the smart speaker device are connected and a second state where the power source and the smart speaker device are disconnected, and a visual indicator configured to indicate when the power switch is in the first state.

Abstract: A system and method may include receiving, at a first node of a circuit electrically coupled to a light emitting diode, a pulsed electrical signal that includes signal current pulses. The system and method may also include enabling discontinuous discharging of a capacitor electrically coupled to the first node during a particular time period between two particular signal current pulses of the pulsed electrical signal.

Abstract: LED backlight circuits for a display and methods for operating the circuits are disclosed. The LED backlight circuit includes a set of drivers and a set of LED strings. A driver can be capable of coupling to any of the LED strings at a given time. Examples of the disclosure can include different configurations of drivers. In some instances, the driver may include an auxiliary transistor that allows the driver to settle before being switched to control a respective LED string. In some examples, the driver can include switches and an idle transistor that can be operated such that a low current path through the driver can exist when the driver is not coupled to a LED string.

Abstract: A switching circuit includes a semiconductor switch having a Gate terminal, and includes first, second, third, and fourth Gate resistors. The Gate resistors have upstream and downstream ends relative to a location of the semiconductor switch or a driven load. The downstream ends connect to the Gate terminal. First, second, third, and fourth buffer switches have Gate terminals and Source terminals, with the Source terminals connected to the upstream ends of the first, second, third, and fourth Gate resistors, respectively. An optional Gate driver integrated circuit (IC) connects to the Gate terminals of the buffer switches. A microcontroller, responsive to circuit measurements, selects switching control values and Gate resistor identities based on the measurements, and transmits switching control signals and a Gate resistor selection signal to select on/off states of the buffer switches and an optimum switching speed for the semiconductor switch.