Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Matsushita Electronics Corporation

Yoshiaki Hachiya

Takashi Kunimatsu

Ryutaro Arakawa

Minoru Fukui

Yuji Yamanishi

Yoshihiro Mori

Makoto Yamada

Kazushige Sugita

Takashi Maniwa

Yuji Ueno

Hiroshi Fujita

Tetsuji Yamashita

Kazuhiko Itoh

Satoru Takahashi

Kazuo Gouda

Ryuma Hirano

Seiki Yamaguchi

Seiji Sogo

Ryutarou Arakawa

An apparatus for controlling plant pests includes a portable case and a light source held in the case. The light source emits ultraviolet light in a predetermined direction. The case includes an installation assembly configured to be installed in a culture medium of the plant so that the predetermined direction is upward. An optical component that removes a wavelength component larger than 340 nm from the ultraviolet light emitted by the light source may also be provided.

Pest control apparatus

A disinfecting method includes irradiating fungi or bacteria with light including violet light having a light emission peak with (i) a full width at half maximum of at most 20 nm and (ii) a peak wavelength included in a range of from 380 nm to 410 nm, inclusive.

Disinfecting method and disinfecting apparatus

A light bulb-shaped lamp according to the present invention includes: a board on which an LED is mounted; a circuit board on which a drive circuit that turns on the LED is mounted; output wires for supplying power for turning on the LED from the drive circuit to the LED; a pedestal; and a potential-stabilizing wire electrically connecting the pedestal to a circuit ground of the drive circuit.

Illumination light source and lighting apparatus

The present invention reduces switching noise generated in a switching control device having a switching element such as a switching power supply in linear linkage with the state of a load of the output and without increasing the control circuit scale which is a factor of cost increase. The present invention adopts a configuration of a control circuit having an ON/OFF circuit that controls the switching element such that one or both of two specified values (upper limit and lower limit) that specify triangular waves of a triangular wave generation circuit that specifies a drive oscillating frequency of the switching element is/are changed in linear linkage with the output load state.

Switching control device

The LED driving semiconductor apparatus for driving at least one LED includes an input terminal, an output terminal, a switching element block and a controller. The input terminal is connected to a high voltage side of a rectifying circuit for rectifying an alternating current voltage, and inputs the voltage from the rectifying circuit. The output terminal is provided for supplying a current to the LED. The switching element block is connected between the input terminal and the output terminal, and has a first switching element. The controller includes a regulator for generating a power source voltage for driving and controlling the switching element block, and a drain current detector for detecting a drain current of the switching element block, and performs on/off control of the first switching element to block the drain current of the switching element block when the drain current reaches a predetermined threshold.

Led driving semiconductor apparatus provided with controller including regulator and drain current detector of switching element block

There is provided a light emitting diode drive apparatus which decreases a conducted emission. The light emitting diode drive apparatus includes a light emitting diode to which a voltage is applied from a voltage source, a choke coil connected in series to the light emitting diode, a rectifier diode connected in parallel to the light emitting diode and the choke coil to supply a back electromotive force generated in the choke coil to the light emitting diode, and a switching drive circuit including a switching element and a control circuit block. The switching element determines whether a current is applied or not applied to the light emitting diode. The control circuit block controls on/off timing of the switching element to control the current flowing into the light emitting diode. The choke coil is connected between the light emitting diode and the switching element.

Light emitting diode drive apparatus

An operating voltage of a control circuit controlling ON/OFF of a switching element of a power supply is supplied from a connection node between a primary winding of a transformer and the switching element. The control circuit includes: an output voltage detection circuit that obtains, from a voltage output from the wave-shaping circuit, a feedback voltage in proportion to a voltage output from the rectifier/smoothing circuit and generates a signal for PWM control of the switching element; and a bottom detection circuit that detects, from the voltage output from the wave-shaping circuit, a bottom level of a ringing voltage. The control circuit switches the switching element from OFF to ON in accordance with a signal output from an oscillator internal to the control circuit or a signal output from the bottom detection circuit.

Switching power supply and semiconductor device used therefor

A reference supply voltage circuit includes a detecting device for detecting a first reference voltage, a comparator, and a preventing circuit for preventing any false operation during pre-operation indefinite time interval. The comparator outputs a signal which controls an operation circuit whose supply voltage is a second reference voltage equal to or lower than the first reference voltage. The preventing circuit maintains the second reference voltage to a circuit reference potential when the first reference voltage is lower than a first predetermined voltage, sets the second reference voltage to a voltage equal to the first reference voltage when the first reference voltage is equal to or higher than the first predetermined voltage and lower than a second predetermined voltage, and sets the second reference voltage to a voltage proportional to the first reference voltage when the first reference voltage is equal to or higher than the second predetermined voltage.

Reference supply voltage circuit using more than two reference supply voltages

A switching control circuit is provided which can increase the off period of a switching element when the on period of the switching element is equal to the sum of the minimum pulse period (blanking period (a fixed period during which drain current is not detected after the switching element is turned on)) and a detection delay period (a period from when the drain current is equal to or higher than a detection criterion to when the switching element is actually turned off) and PWM control is disabled. An off period adjusting circuit generates, when the on period of the switching element is equal to the minimum pulse period, an adjusting signal OFF_C for increasing the off period of the switching element and supplies the signal to an on/off circuit for controlling the periodic on/off operation of the switching element.

Switching control circuit with off period adjustment

An output voltage detection circuit is provided for accurately detecting a secondary side output voltage based on a voltage induced to an auxiliary winding in an isolated switching power supply including a transformer having the auxiliary winding. A voltage waveform processing circuit (-) processes the waveform of the voltage induced to the auxiliary winding (-), a hold circuit (-) holds the voltage peak value after the processing, a secondary side current detection circuit () detects a period during which current passes through a secondary side winding (-), a correction circuit () performs correction to decrease the peak voltage which has been held by the hold circuit (-) during the period, and the corrected voltage is fed back to a control circuit (). Meanwhile, a reset circuit () resets, for a fixed period after the current passes through the secondary side winding (-), the peak voltage having been held by the hold circuit (-).

Output voltage detection circuit, isolated switching power supply, and semiconductor device

The peak current flowing to the switching device drops in a no-load state with PWM control, but because the number of switching operations is constant regardless of the load, further reducing power consumption is difficult. The switching power supply device has a PWM signal generator for generating a PWM signal, a switching device Qfor switching the first supply voltage VIN based on the PWM signal, converters for outputting the difference between a second supply voltage and a reference voltage as a difference signal, and an intermittent oscillation control circuit for stopping the switching operation of the first switching device when the difference signal is less than a predetermined first threshold value (Vp). The PWM signal generator changes the pulse width based on the difference signal to generate the PWM signal.

Switching power supply device

In a switching power supply apparatus, the change in the voltage VOUT at the OUT terminal is transmitted to a V-I conversion circuit via an error amplification circuit and to an I-V conversion circuit, whereby the output voltage signal VL of the I-V conversion circuit is changed. The peak value of the drain current of a switching device changes since VL is used as the reference voltage of an overcurrent detection circuit. VL is transmitted to an intermittent oscillation control circuit having a hysteresis characteristic, and the switching device is subjected to intermittent oscillation. In the switching power supply apparatus, further reduction in power consumption can be attained during standby, particularly in a no-load condition.

Switching power supply apparatus

The present invention relates to a semiconductor device that is employed in a switching power supply for which a higher output is required, prevents noise from the coil, transformer, and so forth and implements a high efficiency power supply. By connecting a current mirror circuit including a p-type MOSFET, an overcurrent detection level tuning circuit, an overcurrent detection circuit, and an intermittent oscillation control circuit to an FB terminal peripheral circuit that is a feedback signal input terminal, PWM control capable of varying the IDRAIN peak value is implemented for the transition from a heavy load state to a light load state and intermittent oscillation control is implemented for the transition between a light load state to a loadless state, such that noise from the coil, transformer, and the like is suppressed and higher efficiency is realized.

Semiconductor device

An output signal of an error amplifier, which has a reference terminal to which a voltage having no temperature characteristics fluctuation is applied and which has a detection terminal to which a voltage detecting terminal VOis connected, is transmitted to the control terminal of a switching element. Voltage fluctuation at the voltage detecting terminal VOis output as a current signal by a V-1 conversion circuit constituted by a current mirror circuit having a constant current source, the switching element, and switching elementsandto a detected signal output terminal PC via the error amplifier. The signal is transmitted to the outside by a optical couplerto control a voltage at an output voltage terminal VOUT. A voltage detection circuit, in which a desired voltage is acquired by controlling voltages at terminals supplied with power, exhibiting lower power consumption and improved voltage detection accuracy and a power supply unit having low ripple voltage and a reduced components count are implemented.

Voltage detection circuit, power supply unit and semiconductor device

A LED driving semiconductor circuit of the present invention includes a first input terminal connected to a light-emitting diode, a switching device block having a first FET and a first switching device, a reference voltage terminal which is connected to the first FET and outputs the reference voltage, a start/stop circuit which outputs a start signal when the reference voltage is equal to or larger than a predetermined value and outputs a stop signal when the reference voltage is less than the predetermined value, a current detection circuit which detects the current flowing through the first switching device, and a control circuit which controls ON/OFF of the first switching device intermittently at the predetermined frequency based on the output signal of the start/stop circuit and the output signal of the current detection circuit so that the constant current flows through the light-emitting diode.

Growing community of inventors

Shiga, Japan

Yoshiaki Hachiya