Abstract: A microcontroller based multifunctional electronic switch using a detection circuit design to convert external control signal into message carrying sensing signal readable to the microcontroller. Based on a time length of sensing signal and a format of the sensing signal received in a preset instant period of time the microcontroller is designed to recognize working modes chosen by the external control signal generated by user, and thereby selecting appropriate working process for execution. The system and method of the present invention may simultaneously be applicable to detection circuit design using infrared ray sensor, electrostatic induction sensor, conduction based touch sensor or push button sensor for performing multifunctions such as controlling on/off switch operation, diming or speed control and delay timer management within the capacity of a single lighting load or an electrical appliance.

Abstract: The present invention relates to a lighting system (1) for providing light in a room (10) comprising first illuminating means (11), a first control unit (12) configured to control the light emitted from the first illuminating means (11) and further configured to receive wireless control communication (14) from a mobile device (13) after being paired with said mobile device, wherein the lighting system (1) further comprises a sensor (15) for detecting presence in the room (10) and for being communicatively connected (16) to said control unit; and wherein said control unit (12) is configured to only allow pairing of a mobile device (13) to said control unit during a predetermined time following a detection of presence in the room by said sensor (15).

Abstract: The invention relates to an illumination system (A) having at least one operating device (1) for operating lighting means, having a control device (10) which is connected by means of an analogue or digital light control bus to the operating device and is designed for transmission of analogue or digital control commands via the light control bus, wherein the control device (1) is designed to control the operating devices (1) in terms of brightness and/or color by means of control commands, wherein furthermore the control device is connected to a IPv6 bus system, the control device (10) is designed to receive IPv6 bus commands via the IPv6 bus system and is designed to transmit a colour command or a brightness command as control command, according to the received IPv6 bus commands, to at least one operating device, and the operating device is designed to adapt the control of the lighting means according to the received colour command or brightness command.

Abstract: A microcontroller based multifunctional electronic switch using a detection circuit design to convert external motion signals into message carrying sensing signals readable to the microcontroller. Based on the time length of sensing signals and the format of the sensing signals received in a preset instant period of time the microcontroller through the operation of its software program codes written in the OTPROM is able to recognize the working modes chosen by the external signal generating user and thereby selecting the appropriate loops of subroutine for execution. The system and method of the present invention may simultaneously be applicable to detection circuit design using infrared ray sensor, electrostatic induction sensor, conduction based touch sensor or push button sensor for performing multifunction such as controlling the on/off switch performance, the diming or speed control and the delay timer management within the capacity of a single lighting device or an electrical appliance.

Abstract: A multiple chip voltage feedback technique allows multiple strings of LED's and current sinks to be efficiently powered by a DC-to-DC voltage converter within an appliance. A connected series of differential amplifiers or multiplexers are used to monitor the voltages between the connected LED's and the current sinks, progressively determine the lowest voltage, and then feed the lowest voltage back to the voltage converter. The DC-to-DC voltage converter monitors this lowest voltage and adjusts its output in order to ensure that the strings have adequate voltage with which to function, even as the LED's have different forward voltages and the strings are asynchronously enabled and disabled.

Abstract: An LED driver controls current through an LED string. The LED driver generates a boosted PWM signal to drive a PWM transistor in the LED current path such that the PWM transistor maintains a substantially constant VGS, thus minimizing turn-on impedance of the PWM transistor. A current mirror circuit controls peak LED current when the PWM transistor is on. A trimming circuit includes a set of programmable switches to couple or decouple trimming transistor from the LED current path, and allowing for fine calibration of the LED current. By maintaining a low resistance and compensating for current mismatch in the LED current path, the LED driver provides efficient power performance and robustness that is particularly beneficial in high current applications.

Abstract: A display circuit includes a first pulse width modulated (PWM) signal line coupled to a first switch, a second PWM signal line coupled to a second switch and the signal line, a transistor coupled to the second signal line between the first signal line and the second switch, a third switch coupled to a third PWM signal line, a fourth switch coupled to a fourth PWM signal line, a fifth switch coupled to a fifth PWM signal line, a light emitting diode (LED) including a red element coupled between the first and third switches, a green element coupled between the first and fourth switches, and a blue element coupled between the first and fifth switches, and an LED including a red element coupled between the second and third switches, a green element coupled between the second and fourth switches, and a blue element coupled between the second and fifth switches.

Abstract: A handheld device includes a backlight driving unit and a power supply circuit for powering the backlight driving unit. The power supply circuit includes a power management unit, a battery, a first electronic switch, a second electronic switch, and a control unit. When a voltage of a second terminal of the second electronic switch is less than a reference voltage of the control unit, the control unit turns on the first electronic switch and turns off the second electronic switch. The backlight driving unit is powered by the battery through the first electronic switch. When the voltage of the second terminal of the second electronic switch is more than the reference voltage of the control unit, the control unit turns off the first electronic switch and turns on the second electronic switch. The backlight driving unit is powered by the PMU through the second electronic switch.

Abstract: An LED driver includes a transformer, current control loop and current adjustment circuit. The primary side of the transformer transfers energy to the secondary side of the transformer responsive to an input signal. The secondary side delivers output current to one or more LEDs at a magnitude corresponding to the amount of energy transferred to the secondary side. The current control loop controls current in the primary side so that the output current equals a reference current signal. The current adjustment circuit injects a current adjustment signal into the current control loop responsive to a phase-cut signal which removes a portion of the input signal. The current control loop also decreases the current in the primary side responsive to the current adjustment signal so that a brightness of each LED connected to the secondary side is decreased by an amount corresponding to the magnitude of the current adjustment signal.

Abstract: In various embodiments, a two-switch flyback power supply may include a transformer having a primary winding and a secondary winding to feed a load; a pair of electronic switches alternatively switchable on and off to connect the primary winding of said transformer to an input line to feed said primary winding of said transformer, wherein at least one of said electronic switches is an electronic switch having a control electrode floating with respect to ground; a capacitive voltage divider arranged between said input line and the ground of the device, with the dividing point of said capacitive voltage divider connected to an intermediate point of said primary winding of said transformer; and an auxiliary secondary winding in said transformer, said auxiliary secondary winding feeding the control electrode of said at least one of said electronic switches.

Abstract: The semiconductor device is included in the LED driving circuit (current regulator) of driving the LED array (with series-connected number m×parallel-connected number n), and is formed of a plurality (n pieces) of LED driving devices of controlling a current (constant-current driving) flowing in each string. A vertical semiconductor device, for example, a vertical MOSFET is used as the LED driving device. Both of a main device functioning as a constant-current driving device and a subsidiary device functioning as a circuit-breaking switch during dimming are formed inside a chip of the device, which are formed of the vertical semiconductor devices. In a first surface of the device, each source region of the main device and the subsidiary device is formed so as to be insulated from each other through an isolation region.

Abstract: An LED driving device includes a DC to DC converter module and a driving module. The DC to DC converter module includes a full-bridge switching circuit for converting a first DC electric power into an AC electric power, a rectifier circuit for converting the AC electric power into a second DC electric power, and a control circuit for modulating pulse phase of the second DC electric power and for controlling switching operation of the full-bridge switching circuit, such that the second DC electric power has a predetermined voltage value. The driving module is operable to receive the second DC electric power, to output a third DC electric power with a predetermined current value for driving an LED module, and to modulate pulse width of the third DC electric power.

Abstract: An LED backlight driving circuit including a boost circuit and a transformer current balance circuit is provided. The boost circuit provides a total current for n LED strings, and the transformer current balance circuit is coupled to the LED strings and includes n?1 transformers. A first LED current-balance-circuit (CBC) includes a switching-transistor connected to a secondary-winding of a first-transformer, and an nth LED CBC includes a switching-transistor connected to a primary-winding of an (n?1)th transformer. An ith (1<i<n, n>2) LED CBC includes a switching-transistor sequentially connected to a primary-winding of an (i?1)th transformer and a secondary-winding of an ith transformer. The passive-transformers are applied in the LED driving circuit to implement current balance/equalization, such that the LED backlight driving circuit is suitable for a system with any odd or even number (greater than 1) of the LED strings connected in parallel, so as to reduce the cost of the system.

Abstract: The semiconductor device is included in the LED driving circuit (current regulator) of driving the LED array (with series-connected number m×parallel-connected number n), and is formed of a plurality (n pieces) of LED driving devices of controlling a current (constant-current driving) flowing in each string. A vertical semiconductor device, for example, a vertical MOSFET is used as the LED driving device. Both of a main device functioning as a constant-current driving device and a subsidiary device functioning as a circuit-breaking switch during dimming are formed inside a chip of the device, which are formed of the vertical semiconductor devices. In a first surface of the device, each source region of the main device and the subsidiary device is formed so as to be insulated from each other through an isolation region.

Abstract: A communications apparatus and techniques are presented for communicating with ballasts or drivers through lighting system power connections in which the power connections are energized with low levels of power to power communications components in the ballast/drivers while the light sources are off and low frequency AC communications signals are transmitted through the power connections.

Abstract: The semiconductor device is included in the LED driving circuit (current regulator) of driving the LED array (with series-connected number m×parallel-connected number n), and is formed of a plurality (n pieces) of LED driving devices of controlling a current (constant-current driving) flowing in each string. A vertical semiconductor device, for example, a vertical MOSFET is used as the LED driving device. Both of a main device functioning as a constant-current driving device and a subsidiary device functioning as a circuit-breaking switch during dimming are formed inside a chip of the device, which are formed of the vertical semiconductor devices. In a first surface of the device, each source region of the main device and the subsidiary device is formed so as to be insulated from each other through an isolation region.

Abstract: A circuit for supplying a light source (L) such as a high flux (HF) LED with Pulse Width Modulation (PWM) dimming capability includes: a rectifier (10) for receiving an input bipolar PWM modulated signal (v) representative of a desired dimming level for the light source (L) and produce therefrom a rectified signal; a current regulator (14) to receive the rectified signal and produce therefrom a supply current for the light source (L); and a control module (16) sensitive to the input bipolar PWM modulated signal (v) to control the current regulator (14) to produce a PWM modulated supply current for the light source (L); and a capacitor (18) arranged between the rectifier (10) and the current regulator (14) to stabilize the rectified signal. The circuit typically includes ancillary circuitry (12), such as a microcontroller, connected to the capacitor to be supplied with the rectified signal as stabilized by the capacitor (18).

Abstract: A light-emitting device capable of being powered by an AC power supply or an unregulated DC power supply is disclosed. The light-emitting device, in an aspect, is coupled to a controller, a light-emitting diode (“LED”) array, and a power supply, wherein the power supply can be an AC power source or an unregulated DC power source. While the power supply provides electrical power, the controller generates various LED control signals in response to power fluctuation of the electrical power. The LED array allows at least a portion of LEDs to be activated in accordance with the logic states of the LED control signals.

Abstract: Disclosed are light emitting diode circuits employing first sub-circuits including first light emitting diodes and connected in parallel with second sub-circuits including second light emitting diodes and switches for, in conducting states, switching on the second light emitting diodes and switching off the first light emitting diodes and for, in non-conducting states, switching off the second light emitting diodes and switching on the first light emitting diodes. The first sub-circuits and the second sub-circuits have different signal characteristics such as different minimum threshold voltages to be realized by using different kinds of light emitting diodes, by using different total numbers of serial light emitting diodes, or by adding threshold voltage elements to the first sub-circuits.

Abstract: A light source driving device for driving plural light sources is provided. The light source driving device includes a voltage booster to boost a voltage from a power source to supply the boosted voltage to each of the plural light sources; a constant current driver to regularly hold driving current of each of the plural light sources constant; a load to consume substantially the same power as the plural light sources; and a switch to selectively connect either the load or the plural light sources with the voltage booster and the constant current driver so that the load or the plural light sources are interposed between the voltage booster and the constant current driver.

Abstract: When the cathode of a light emitting thyristor is at the low (L) level, voltage is applied between the anode and cathode of the light emitting thyristor. In addition, because the gate of each thyristor and the gate of each light emitting thyristor are connected to each other in a self scanning circuit 100, voltage is also applied between the gate and cathode of the thyristor. At this time, by selectively turning only the gate of the light emitting thyristor, which is instructed by the self scanning circuit to emit light, to the high (H) level, the light emitting thyristor that is instructed is turned on. In particular, because an output signal of a clock driving circuit is differentiated by an RL differential circuit to generate an undershoot or overshoot waveform, the number of output terminals of the clock driving circuit can be reduced.

Abstract: A monolithic light-emitting device and driving method therefore includes a plurality of light-emitting diodes, array-arranged monolithically on a single substrate. The light-emitting diodes include a pn junction-containing semiconductor material and a phosphor-containing layer passing light emitted from the semiconductor material, absorbing part, or whole of the light for conversion into light having a different wavelength. The array is constituted of a light-emitting diode group consisting of m (m?2) pieces of the light-emitting diode, the light emitting diode group being constituted of N types (N?2, providing N?m) of light-emitting diodes, each having either one of preset N types of light-emitting spectrum patterns. An average light-emitting spectrum from the whole array can be changed by regulating a power supplied to the light-emitting diodes for each light-emitting diode group sorted according to the type of the light-emitting spectrum pattern.

Abstract: There is provided a light-emitting-element driving circuit which comprises a light-emitting circuit unit in which a plurality of current paths in each of which a light-emitting element and a first switching element are connected in series are placed in parallel with each other between a power supply terminal connected to an input power supply and a common terminal, a common circuit unit in which a second switching element and a constant current source which supplies a predetermined current which is defined in advance are connected in series and which is placed between the common terminal and a ground terminal which is grounded, and a plurality of third switching elements each of which is placed between an anode terminal of the respective light-emitting element of the light-emitting circuit unit and ground, wherein a switching control is applied for the first switching elements, the second switching element, and the third switching elements.

Abstract: A controlling apparatus for controlling a plurality of LED strings and related light modules is disclosed, wherein each of the plurality of LED strings has a first terminal being electrically connected to an operating voltage. The controlling apparatus includes: a plurality of transistors, each having a control terminal, a first terminal, and a second terminal, wherein the first terminal of each transistor is electrically connected to a second terminal of a corresponding string of the plurality of LED strings, and the second terminals of the plurality of transistors are respectively grounded through a plurality of impedance elements; and a transistor controller, electrically connected to the control terminals of the plurality of transistors, for controlling a current of the first terminal of each transistor by adjusting an input signal of the control terminal of the transistor according to a voltage at the second terminal of the transistor.

Abstract: A device for driving a plurality of light emitting diodes includes a plurality of light emitting diode groups in series; a current providing unit for providing a current to the plurality of light emitting diode groups; and at least one current path controller in parallel with a corresponding one of the light emitting diode groups for turning off the corresponding one of the light emitting diode groups in accordance with a control signal.

Abstract: Describe is a device for a multiplexing, output current-sensed, boost converter circuit which may be used as an LED driver. A boost converter LED driver circuit using a single set of passive external LC components for controlling the current through, and thus the output of, one and more than one bank of LEDs. The present invention allows for regulated current in one and more than one bank of LEDs by sensing current in the controller. The output voltage of a switcher adjusts it's level automatically until the current to the LEDs is set to the desired LED threshold requirement.

Abstract: A three-component, protective headgear or helmet, and circuits therefor is provided with a battery-powered LED head lamp, which may be used by construction workers, search and rescue persons, cyclists, police, fireman, and the like. The battery may be replaceable or rechargeable and has long-term, uniform output characteristics driven by unique circuitry.

Abstract: A dimmer circuit arrangement is disclosed including a second control circuit (40) for controlling the operation of a triac (50) for delivering current to a load (60), and a first control circuit (10) for controlling the operation of an IGBT power semiconductor switch (20) for controlling the rate of rise of load voltage. The first control circuit also controls the operation of the second control circuit.

Abstract: A driver circuit for a DC light source supplies a voltage generated by a DC-to-DC converter for a plurality of lamp strings connected in parallel and a plurality of driving currents generated by a current mirror for the lamp strings, such that the lamp strings may have well controlled or uniform brightness.

Abstract: A three-component, protective headgear or helmet is provided with a battery-powered LED head lamp, which may be used by construction workers, search and rescue persons, cyclists, police, fireman, and the like. The battery may be replaceable or rechargeable and has long-term, uniform output characteristics driven by unique circuitry.

Abstract: A light emitting code (“LED”) circuit includes a plurality of light emitting diodes connected in a hybrid parallel-series configuration, and a current regulating circuit that includes a current regulating element connected to a first chain of the plurality of chains of LEDS, and a plurality of current mirroring elements, each current mirroring element being connected to a respective chain of the plurality of chains of LEDs.

Abstract: A circuit and method for providing closed loop control using constant current switching techniques is disclosed herein. By controlling the current supplied to high intensity light emitting diodes (LEDs) using the techniques and circuits described, high intensity LEDs can be operated at or near their maximum capacity without danger of overloading the LEDs, and without using excess amounts of current. A circuit as described herein, has multiple high side switches, each of which is connected to an LED array. The LED arrays are in turn connected through an inductor to a current switching control section that switches current to ground, or recirculates the current to maintain LED current flow within a desired range.

Abstract: An integrated LED driving device for multiple LED strings which employs a single linear regulator or other controller and a multiple-output current mirror which is almost independent of the DC input voltage source, almost independent of the transistor's or MOSFET's variations from the semiconductor integration process, and almost independent of temperature variation. The multiple-output current mirror includes a plurality of transistors or MOSFETs each of which are integrated on the same substrate, with identical width-to-length channel ratios and with identical source and gate connections. The integrated LED driving device provides for automatic current sharing in a DC mode and, alternately, with minimized phase delays in a PWM mode. The mirror-output current mirror may include mirror-cascode transistor pairs.

Abstract: An LED lamp device of the invention includes a power supply unit (102, 103) supplied with an alternating-current power supply voltage, and an LED lamp (106) constituted by one or a plurality of serially connected LEDs connected to output terminals of the power supply unit (102, 103). The power supply unit (102) obtains a rectified wave of the alternating-current power supply voltage, admits electric power for only part of a time period in which the voltage of the rectified wave corresponding to each half period of the wave of the alternating-current power supply voltage is higher than or equal to a predetermined value, and uses the electric power as power for lighting the LED lamp (106).

Abstract: A hand held light apparatus is disclosed. The apparatus has a handle portion, a central portion, and a cap portion for mounting a lamp. An electric circuit, preferably located in the central portion, connects the lamp with a power source, preferably batteries in the handle portion, to activate the lamp in different selectable modes. The modes include at least a continuous on mode and an intermittent flashing mode. The apparatus is arranged to allow a member in an audience to show his or her appreciation of a performance by raising the apparatus and activating it in one or its operational modes. With its different operational modes, the apparatus also functions as an emergency signal indicator, and further can be made to serve in the way of a conventional flashlight.

Abstract: The invention relates to an electronic ballast for a discharge lamp, comprising a drive circuit supplying high-frequency current to the lamp and including two power switches (V1, V2) and control circuits therefor for controlling the power switches, such that the parallel half-waves of the lamp current pass through a first power switch (V1) and the reverse half-waves through a second power switch. Each power switch (V1; V2) is provided with its own, independently operating control circuit and each control circuit is provided with means (R1, R3, R8, R7) for sensing a current passing through and a voltage prevailing across the appropriate power switch (V1; V2) as well as with means (V3; V4) for controllably bringing the appropriate power switch (V1; V2) to a conducting state as a certain voltage prevails thereacross and to a non-conducting state as soon as a current passing therethrough reaches a certain threshold value (Ik; Ikl).

Abstract: A circuit for lighting a fluorescent lamp. The present invention takes into account the fastidious characteristics of the fluorescent lamp, and during the momentary lighting of the fluorescent lamp. In order to reduce the temperature fluctuations, a separate pre-heating power is supplied. The circuit includes: a first resonance circuit consisting of a first capacitor connected to the opposite ends of the fluorescent lamp, a resonance inductor, a second capacitor, a first switch and a DC power source, serially connected; a second resonance circuit consisting of a second switch, a first capacitor, a resonance inductor, a third capacitor and a DC power source, serially connected; a switch control circuit for activating the first and second switches in an alternate manner. Before the lighting of the fluorescent lamp, the first and second resonance circuits are put to a resonance state, while, after the lighting of the fluorescent lamp, the resonance is eliminated.

Abstract: A driving system for a plasma panel display which uses VFETs for output switches controls the transition time of an output waveform to a constant time. Transformerless circuitry for communicating low voltage digital logic signals across a floating boundary to VFET control circuitry is provided. Low voltage control circuitry is isolated from high voltage sources by semiconductor circuitry which eliminates the need for transformer isolation techniques. In an alternative embodiment, the transition of an output waveform is controlled at a constant slew rate.

Abstract: An electronic ballast for energizing one or more gaseous-discharge lamps and for regulating the power consumed thereby, the ballast including a power supply for providing a source of DC power between a pair of outputs, a pair of transistors connected as switches in series between the power-supply outputs, the transistors for selectively coupling to the juncture thereof positive and negative potentials, a voltage-conditioning and current-limiting network for energizing the lamp from the potential developed between the transistor juncture and a power-supply common, and a pulse generator for developing pulses for driving each of the transistors in turn whereby a potential is developed at the transistor juncture which alternates as positive-going and negative-going pulses each separated by a dead time, the pulse generator for monitoring the power consumption level of the lamp and responsive thereto operative to vary the frequency and/or the width of the transistor driving pulses whereby the lamp consumption is re