Abstract: In a power supply device 1 including a switching element 12 and a control section 11 configured to control the switching element 12, the control section 11 receives an input of a first signal fluctuating according to an output voltage of the power supply device 1 and fixed with respect to an input voltage of the power supply device 1 and a second signal, the amplitude of which fluctuates according to the input voltage of the power supply device 1, and controls ON or OFF of the switching element 12 according to time until a value of the second signal reaches a value of the first signal.

Abstract: To a constant-current power supply whose output current can be variably set, light emitting modules can be connected in parallel. A control unit recognizes connection information outputted from an information output unit provided in each of the light emitting modules and varies the output current of the constant-current power supply. Drive can be controlled in response to a state of the connected light emitting modules such as the connecting number of light emitting modules.

Abstract: To a constant-current power supply whose output current can be variably set, light emitting modules can be connected in parallel. A control unit recognizes connection information outputted from an information output unit provided in each of the light emitting modules and varies the output current of the constant-current power supply. Drive can be controlled in response to a state of the connected light emitting modules such as the connecting number of light emitting modules.

Abstract: To a constant-current power supply whose output current can be variably set, light emitting modules can be connected in parallel. A control unit recognizes connection information outputted from an information output unit provided in each of the light emitting modules and varies the output current of the constant-current power supply. Drive can be controlled in response to a state of the connected light emitting modules such as the connecting number of light emitting modules.

Abstract: A light-emitting device and an illumination apparatus are disclosed. A plurality of LED elements are connected in series between positive and negative lines, and first bypass capacitor is connected in parallel to the LED elements respectively. Each series circuit of a predetermined number of LED elements is connected in parallel to second bypass capacitors. As a result, with the negative power line set as a grounding point, the AC impedance at connection points of the series circuit of the LED elements against the ground is reduced. Thus, the erroneous lighting or “flicker” of each LED which otherwise might be caused by an external noise is prevented.

Abstract: A detection circuit according to embodiments includes a first circuit and a second circuit. The first circuit is turned OFF when an AC voltage to be input to a pair of input terminals is smaller than a prescribed value, and is turned ON when the AC voltage is equal to or higher than the prescribed value. The second circuit detects whether the AC voltage is an AC voltage leading-edge controlled by a dimmer, an AC voltage trailing-edge controlled by the dimmer, or an AC voltage having a continuous phase on the basis of at least one of the value of voltage and a gradient of the first circuit when the first circuit is turned ON while the first circuit is in the OFF state.

Abstract: Disclosed is an interface circuit including a rectifier circuit, a detection circuit, a first circuit, and a second circuit. The rectifier circuit rectifies an AC voltage input between a pair of input terminals. The detection circuit detects the AC voltage and outputs the result as a detection voltage. The first circuit is controlled to be turned on or off on the basis of an input first control signal, to cause a first current to flow between the input terminals in an on state and to cut off the first current in an off state. The second circuit is controlled to be turned on or off on the basis of an input second control signal, to allow a second current greater than the first current to flow between the input terminals in an on state and to cut off the second current in an off state.

Abstract: According to one embodiment, a power supply device includes a full-wave rectifier, a power converting circuit, and a partial smoothing circuit. The power converting circuit converts an output of the full-wave rectifier into a direct-current voltage according to a switching action of a switching element. The partial smoothing circuit includes, in series, a capacitor and a first diode connected in polarity opposite to output polarity of the full-wave rectifier. The partial smoothing circuit is provided on an output side of the full-wave rectifier in parallel to the power converting circuit. In the partial smoothing circuit, the capacitor is charged according to the switching action of the switching element of the power converting circuit. The partial smoothing circuit supplies charged electric of the capacitor to the power converting circuit via the first diode in a trough portion of an output voltage of the full-wave rectifier.

Abstract: There is provided a lighting fixture 11 capable of efficiently radiating heat of a lamp device 14 attached to a socket device 13. By attaching the lamp device 14 to the socket device 13, a cap portion 38 of the lamp device is brought into contact with a fixture body 12, and pressed against and brought into contact with the fixture body 12 by an elastic body 30. Heat generated by lighting of LEDs 35 of the lamp device 14 is conducted from the cap portion 38 to the fixture body 12 and efficiently radiated.

Abstract: The present invention provides a pair of input terminals to which AC voltage is input, the AC voltage being phase-controlled by a dimmer for phase-controlling AC voltage of an AC source; a damping circuit which has a resistor inserted to a position, into which input current flows from the AC source via the dimmer in series, and a capacitor and an inductor which form a closed circuit together with the AC source and the dimmer, and suppresses high-frequency vibration generated in the dimmer when a phase control element of the dimmer is turned on; and an LED lighting circuit which rectifies AC voltage phase-controlled and input via the pair of input terminals, converts DC output voltage, which is obtained by rectification, so that the voltage adapts to a load, and lights the LED.

Abstract: To a constant-current power supply whose output current can be variably set, light emitting modules can be connected in parallel. A control unit recognizes connection information outputted from an information output unit provided in each of the light emitting modules and varies the output current of the constant-current power supply. Drive can be controlled in response to a state of the connected light emitting modules such as the connecting number of light emitting modules.

Abstract: To a constant-current power supply whose output current can be variably set, light emitting modules can be connected in parallel. A control unit recognizes connection information outputted from an information output unit provided in each of the light emitting modules and varies the output current of the constant-current power supply. Drive can be controlled in response to a state of the connected light emitting modules such as the connecting number of light emitting modules.

Abstract: A switching power source device includes: a direct power source; and a chopper circuit including a pair of input terminals connected to the direct power source and a pair of output terminals connected to a load, the chopper circuit including a first inductor, a second inductor magnetically coupled to the first inductor, a third inductor connected to the first inductor, a switching element causing an augmented current to flow from the direct power source to the first and third inductors while turned on, a constant current element connected to the switching element in series, a rectifier element causing a reduced current to flow through the first and third inductors while the switching element is turned off, and a drive circuit controlling and turning off a gate voltage of the switching element after the switching element is turned on and the augmented current reaches a constant current element saturated state.

Abstract: According to one embodiment, a lighting circuit includes a first power supply circuit, a first detecting circuit, a first control circuit, and a first protecting circuit. The first power supply circuit is supplied with power from a first power supply and outputs a direct current flowing in a first direction. The first detecting circuit detects a first detection value of an electric current flowing between the first power supply circuit and an output terminal. The first control circuit compares a first detection value detected by the first detecting circuit with a reference value and controls the first power supply circuit. The first protecting circuit is connected to the first detecting circuit and reduces an absolute value of the first detection value if an electric current flows in a direction opposite to the first direction.

Abstract: A lighting fixture capable of efficiently radiating heat of a lamp device may be configured to be attached to a socket device. In some examples, by attaching the lamp device to the socket device, a cap portion of the lamp device is brought into contact with a fixture body, and pressed against and brought into close contact with the fixture body by an elastic body. Heat generated by lighting of LEDs of the lamp device is conducted from the cap portion to the fixture body and efficiently radiated.

Abstract: A lighting fixture capable of efficiently radiating heat of a lamp device may be configured to be attached to a socket device. In some examples, by attaching the lamp device to the socket device, a cap portion of the lamp device is brought into contact with a fixture body, and pressed against and brought into close contact with the fixture body by an elastic body. Heat generated by lighting of LEDs of the lamp device is conducted from the cap portion to the fixture body and efficiently radiated.

Abstract: To a constant-current power supply whose output current can be variably set, light emitting modules can be connected in parallel. A control unit recognizes connection information outputted from an information output unit provided in each of the light emitting modules and varies the output current of the constant-current power supply. Drive can be controlled in response to a state of the connected light emitting modules such as the connecting number of light emitting modules.

Abstract: According to one embodiment, a power supply for lighting includes a rectifying circuit, a smoothing capacitor, and a current control circuit. The rectifying circuit rectifies a phase-controlled alternating-current voltage supplied to between a pair of input terminals. The smoothing capacitor is connected to a high-potential terminal and a low-potential terminal of the rectifying circuit. A first electric current flows to the current control circuit in a period when an absolute value of the alternating-current voltage is lower than a specified value. After a second electric current larger than the first electric current flows when the absolute value of the alternating-current voltage increases to be equal to or larger than the specified value, the current control circuit is shut off to reduce a current value to be smaller than the second electric current until the absolute value of the alternating-current voltage decreases to be lower than the specified value.

Abstract: A power supply for illumination includes a detection circuit and a control circuit. The detection circuit compares an AC voltage whose phase is controlled with a first threshold voltage so as to detect a variation in a conduction state of phase control in the AC voltage, and compares the AC voltage with a second threshold voltage lower than the first threshold voltage so as to detect a zero-cross point of the AC voltage, thereby detecting a conduction period of the phase control. The control circuit outputs an output current according to the duration of the conduction period.

Abstract: A lighting fixture capable of efficiently radiating heat of a lamp device may be configured to be attached to a socket device. In some examples, by attaching the lamp device to the socket device, a cap portion of the lamp device is brought into contact with a fixture body, and pressed against and brought into close contact with the fixture body by an elastic body. Heat generated by lighting of LEDs of the lamp device is conducted from the cap portion to the fixture body and efficiently radiated.