Abstract: A light emitting drive device has an output voltage supply unit, and an emergency drive unit. The output voltage supply unit generates an output voltage from an input voltage on the basis of a control signal transmitted from a control unit, and supplies at least one light emitting element with the output voltage. In the cases where the emergency drive unit received a signal indicating abnormality of the control unit, the emergency drive unit lights the whole or a part of the at least one light emitting element irrespective of the control signal transmitted from the control unit.
Abstract: A two-dimensional photonic-crystal surface-emitting laser 10 includes: a two-dimensional photonic crystal (two-dimensional photonic crystal layer 12) including a plate-shaped base body 121 having a predetermined size in which modified refractive index areas 122 whose refractive index differs from the base body are periodically arranged in a two-dimensional pattern; an active layer 11 provided on one side of the two-dimensional photonic crystal; and first and second electrodes 15 and 16 facing each other across the two-dimensional photonic crystal and the active layer 11, for supplying an electric current to the active layer 11. The modified refractive index areas 122 are provided in such a manner that the in-plane occupancy of those areas 122 in the base body 121 decreases, or the lattice constant for those areas 122 increases, in the direction from an outer edge toward the center of a current passage region 21 which is a region where the electric current passes through the two-dimensional photonic crystal.
Abstract: A circuit element includes an upper switching device, a lower switching device, an upper diode device, and a lower diode device. An upper drain is connected to a first terminal connected to a positive electrode of a power supply, and an upper source is connected to a third terminal. A lower drain is connected to a fourth terminal, and a lower source is connected to a second terminal connected to a negative electrode of the power supply. An upper anode is connected to the fourth terminal, and an upper cathode is connected to the first terminal. A lower anode is connected to the second terminal, and a lower cathode is connected to the third terminal. The third terminal and the fourth terminal are arranged so as to be able to be short-circuited outside of a package.
Abstract: A semiconductor device includes a semiconductor chip and a plurality of leads. The leads include a first lead including a supporting portion for mounting the semiconductor chip, and a projecting portion which projects in a first direction from the supporting portion. A second lead extends in a second direction non-parallel with the first direction, and one or more third leads extends in the second direction, such that a line extending in a third direction perpendicular to the first direction passes through the second lead and the one or more third leads. The second lead includes a first portion and a second portion, the first portion having a width larger than the second portion, the first portion having one side parallel to the first direction, and the first portion located between the second portion and the first lead.
Abstract: A secondary-side module comprises: a synchronous rectification controller that controls a synchronous rectification transistor; and a shunt regulator that generates a current that corresponds to the difference between an output voltage VOUT of a DC/DC converter and the target value of the output voltage, which are housed in a single package. The multiple pins to be connected to the shunt regulator are all laid out along a first side of the package.
Abstract: A nitride semiconductor device includes a silicon substrate. A nitride semiconductor layer is formed over the silicon substrate. A gate electrode is formed over the nitride semiconductor layer so as to have a first ring-shaped portion and a second ring-shaped portion connected to the first ring-shaped portion. A first finger electrode is surrounded by the first ring-shaped portion. A second finger electrode is surrounded by the second ring-shaped portion. A third finger electrode is interposed between the first ring-shaped portion and the second ring-shaped portion.
Abstract: A primary side controller for controlling a switching transistor on a primary side of an isolated DC/DC converter, includes: a low voltage state detecting circuit configured to detect a low voltage state in which an output voltage of the DC/DC converter is lower than a predetermined value; and a pulse width modulator configured to generate a pulse signal whose ON time is adjusted depending on a feedback signal from a secondary side, wherein a period of the pulse signal in the low voltage state is longer than a period of the pulse signal in a non-low voltage state in which the output voltage is higher than the predetermined value.
Abstract: A slew rate control device for controlling a slew rate, includes: a setting part configured to set a voltage value used to determine the slew rate; and a control part configured to control the slew rate, based on the voltage value set by the setting part, so that the slew rate becomes slower as an output voltage of a power supply approaches from a transition starting voltage to a target voltage.
Abstract: The power module includes: a first metallic circuit pattern, a semiconductor device disposed on the first metallic circuit pattern; a leadframe electrically connected to the semiconductor device; and a stress buffering layer disposed on an upper surface of the semiconductor device, and capable of buffering a CTE difference between the semiconductor device and the leadframe. The leadframe is connected to the semiconductor device via the stress buffering layer, a CTE of the stress buffering layer is equal to or less than a CTE of the leadframe, and a cross-sectional shape of the stress buffering layer is L-shape. There is provided: the power module capable of realizing miniaturization and large current capacity, and reducing cost thereof by using leadframe structure, and capable of reducing a variation in welding and improving a yield without damaging a semiconductor device; and a fabrication method for such a power module.
Abstract: A semiconductor light emitting device (A) includes an elongated substrate (1) formed with a through-hole (11), a first, a second and a third semiconductor light emitting elements (3R, 3G, 3B) mounted on the main surface of the substrate (1), and an electrode (2R) electrically connected to the first semiconductor light emitting element (3R) and extending to the reverse surface of the substrate (1) via the through-hole (11). The first semiconductor light emitting element (3R) and the through-hole (11) are positioned between the second semiconductor light emitting element (3G) and the third semiconductor light emitting element (3B) in the longitudinal direction of the substrate (1). The second semiconductor light emitting element (3G) is arranged closer to one end of the substrate (1), whereas the third semiconductor light emitting element (3B) is arranged closer to the other end of the substrate (1).
Abstract: A switch drive circuit drives a full-bridge output stage connected to a transformer to alternately switch between a first cycle in which a current in a first direction is supplied to the transformer and a second cycle in which a current in a second direction is supplied to the transformer. The switch drive circuit includes a mode in which a dead time of the output stage is set in accordance with a magnitude of a current flown in one of the first and second cycles, the dead time becoming an operation changing factor in the other cycle. Or, the switch drive circuit includes a mode in which the dead time of the output stage is set in accordance with a magnitude of an average current obtained by averaging currents flown in the first and second cycles. Or, the switch drive circuit switches between these modes in accordance with a signal.
Abstract: Disclosed is a signal transmission circuit device (200) including a feedback signal transmission unit (210) that feeds back a control output signal (Sout) as a feedback signal (Sf) to an input side circuit (200A). A logical comparison circuit (212) detects “mismatch” between input and output by performing logical comparison between a control input signal (Sin) and the feedback signal (Sf). When a state of “mismatch” between input and output occurs, a first pulse generating circuit (202) or a second pulse generating circuit (204) outputs a first correction signal (Sa1) or a second correction signal (Sa2) corresponding to a potential (high level or low level) of the control input signal (Sin), and corrects the control output signal (Sout) to the same potential (high level or low level) as the control input signal (Sin). With such configuration, the mismatch between input and output can be automatically corrected.
Abstract: A nonvolatile semiconductor storage device has floating-gate memory cells and a memory control circuit which controls them. During programming operation of the memory cells, the memory control circuit makes the potentials at the backgate and source of the memory cells equal. For example, during programming operation of the memory cells, the memory control circuit short-circuits together the backgate and source of the memory cells. For another example, during programming operation of the memory cells, the memory control circuit switches from a state where the potentials at the backgate and source of the memory cells are equal to a floating state.
Abstract: A rectifier IC seals, in a single package, a first transistor chip which integrates a first transistor, a second transistor chip which integrates a second transistor and a controller chip which detects a first node voltage and a second node voltage of each of the transistors so as to perform on/off control on the transistors, and the rectifier IC functions as a secondary-side rectification means of an isolated switching power supply.
Abstract: A constant voltage generating circuit includes an ED-type reference voltage supply that generates a predetermined constant voltage by using a first transistor of depletion-type and a second transistor of enhancement-type that are connected in series between a power supply terminal and a ground terminal, and a third transistor a source of which is connected to an output terminal for the constant voltage, a drain of which is connected to the power supply terminal or the ground terminal, and a gate of which is connected to a connection node between the first transistor and the second transistor.
Abstract: A chip capacitor and a method for manufacturing the chip capacitor, where the chip capacitor includes a substrate, a first external electrode disposed on the substrate, a second external electrode disposed on the substrate, capacitor elements formed on the substrate and connected between the first external electrode and the second external electrode, and fuses that are formed on the substrate, are each interposed between the capacitor elements and the first external electrode or the second external electrode, and are capable of disconnecting each of the capacitor elements.
Abstract: A regulator includes: a first transistor connected between an input terminal and an output terminal; a feedback circuit configured to control a control voltage of a control electrode of the first transistor such that a voltage of the output terminal approaches a target voltage according to a feedback voltage proportional to the voltage of the output terminal; a second transistor having one end connected to the input terminal and a control electrode to which the control voltage is applied in common with the first transistor; and a clamp circuit configured to set the other end of the second transistor to a voltage determined by the voltage of the output terminal.
Abstract: The semiconductor device according to the present invention includes a ferroelectric film and an electrode stacked on the ferroelectric film. The electrode has a multilayer structure of an electrode lower layer in contact with the ferroelectric film and an electrode upper layer stacked on the electrode lower layer. The electrode upper layer is made of a conductive material having an etching selection ratio with respect to the materials for the ferroelectric film and the electrode lower layer. The upper surface of the electrode upper layer is planarized.
Abstract: This electronic compass has a magnetic sensor for detecting two predetermined axis components out of the three geomagnetic axis components in a location and generating biaxial magnetic detection data corresponding to the magnitudes of the components, an acceleration sensor for detecting three axis components of the acceleration thereof and generating triaxial acceleration detection data corresponding to the three axis components, and an azimuth angle detection unit for calculating assumed magnetic detection data corresponding to the one remaining undetected axis component of the three geomagnetic axis components from the biaxial magnetic detection data, the triaxial acceleration detection data, and the magnitude and the magnetic dip of the geomagnetic field and detecting an azimuth angle by determining the component of the geomagnetic field parallel to the surface of the earth using the assumed magnetic detection data.