Abstract: In a semiconductor package, a stamp is provided on at least one of at least a pair of opposed sides on an outer peripheral portion in contact with an edge of the package, which is a blank space up to now. With this configuration, the amount of stamp can be increased even in a narrow stamp area.

Abstract: First and second signal processing units are each configured by an IC, so that the circuit space occupying in a receiver apparatus can be reduced. The signal path can be shortened from a BPF section inputting a program signal coming from a broadcasting station to a demodulation section compared with the related art. The transmission loss on the signal path can be thus reduced compared with the related art. The possible route for noise entering from the outside to the first and second signal processing units can be made as short as possible. This enables to reduce the noise entering from the outside, and prevents the signals coming over the signal path from being attenuated by the noise so that the signal reception sensitivity can be increased.

Abstract: A power converting apparatus having a gate drive circuit including a push-pull circuit consisting of two transistors at its output stage; a diode connected in series with the push-pull circuit; a gate power source connected in parallel with the series circuit of the push-pull circuit and the diode; a negative voltage generating circuit connected in parallel with the push-pull circuit; a transistor connected between the output terminal of the negative voltage generating circuit and the negative terminal of the gate power source, wherein the output voltage of the push-pull circuit is switched from positive polarity to negative polarity and vice versa depending on the signal applied to the base terminals of the transistors.

Abstract: A bi-directional DC-DC converter has a transformer for connecting a voltage type full bridge circuit connected to a first power source and a current type switching circuit connected to a second power source. A voltage clamping circuit constructed by switching elements and a clamping capacitor is connected to the current type switching circuit. The converter has a control circuit for cooperatively making switching elements operative so as to control a current flowing in a resonance reactor.

Abstract: A bi-directional DC-DC converter uses a transformer for both step-down and step-up operations. A switching frequency for operating a switching device is set separately for the step-down and step-up operations. When, for example, the switching frequency during the step-up operation is lower than the switching frequency during the step-down operation, the range in which the duty ratio in PWM control can be controlled is widened, compensating for step-up ratio insufficiency. Conversely, step-down ratio insufficiency is compensated for by making the switching frequency during the step-down operation lower than the switching frequency during the step-up operation.

Abstract: A bi-directional DC-DC converter has a transformer for connecting a voltage type full bridge circuit connected to a first power source and a current type switching circuit connected to a second power source. A voltage clamping circuit constructed by switching elements and a clamping capacitor is connected to the current type switching circuit. The converter has a control circuit for cooperatively making switching elements operative so as to control a current flowing in a resonance reactor.

Abstract: A transmission power of a communication apparatus can be appropriately determined in accordance with different communication multiplicities between two or more communication channels. A mobile communication system in which a base station apparatus and a mobile station apparatus communicate with each other by using configuration channels (CCH) or random access channels (RACH) includes a transmission power control part for determining basic data of the transmission power in RACH of the mobile station apparatus in accordance with a communication status in CCH, and a transmission power determining part for determining the transmission power in RACH of the mobile station apparatus by changing the basic data at least in accordance with the communication multiplicity of RACH.

Abstract: A bi-directional DC-DC converter has a transformer for connecting a voltage type full bridge circuit connected to a first power source and a current type switching circuit connected to a second power source. A voltage clamping circuit constructed by switching elements and a clamping capacitor is connected to the current type switching circuit. The converter has a control circuit for cooperatively making switching elements operative so as to control a current flowing in a resonance reactor.

Abstract: A unidirectional DC-DC converter and method of control thereof. The converter includes a DC power-supply, a buck converter circuit having a first main switching element, a boost converter circuit having a second main switching element, a first snubber capacitor, a first inversely-parallel diode, a control device, and an output diode.

Abstract: A bi-directional DC-DC converter has a transformer for connecting a voltage type full bridge circuit connected to a first power source and a current type switching circuit connected to a second power source. A voltage clamping circuit constructed by switching elements and a clamping capacitor is connected to the current type switching circuit. The converter has a control circuit for cooperatively making switching elements operative so as to control a current flowing in a resonance reactor.

Abstract: A bidirectional DC-DC converter 10 has smoothing capacitors Cs1 and Cs2, a smoothing reactor Ls, resonant reactors Lr1 and Lr2, and a resonant capacitor Cr, as well as insulated gate bipolar transistors (IGBTs) Q1, Q2, and Q3 to which buffer capacitors C1, C2, and C3 are connected in parallel and diodes D1, D2, and D3 are connected in a back-to-back configuration. After part of the energy stored in the smoothing reactor Ls and/or resonant reactors Lr1 and Lr2 draws charges in the buffer capacitor C3 and is stored in the resonant capacitor Cr, the energy is stored in the resonant reactors Lr1 and Lr2. The energy is used to draw charges in the buffer capacitors C1 and C2, achieving soft switching of IGBTs Q1, Q2, and Q3.

Abstract: The present invention includes a plurality of mounting portions on which a semiconductor element is mounted, a plurality of electrodes to which the semiconductor elements that are mounted on each of the mounting portions are electrically connected, a corner portion which connects the plurality of mounting portions and which has a hanging lead piece that supports the mounting portions and an electrode connection piece that connects the plurality of electrodes, and a half-blanking portion that has a concave portion formed in a thickness direction of the lead frame and a protrusion formed at a position corresponding to the concave portion, and which is covered with a sealing resin material that seals the semiconductor element. A stress-dispersing portion for dispersing stress that arises, when the half-blanking portion is formed, is provided in the corner portion.

Abstract: A bi-directional DC-DC converter uses a transformer for both step-down and step-up operations. A switching frequency for operating a switching device is set separately for the step-down and step-up operations. When, for example, the switching frequency during the step-up operation is lower than the switching frequency during the step-down operation, the range in which the duty ratio in PWM control can be controlled is widened, compensating for step-up ratio insufficiency. Conversely, step-down ratio insufficiency is compensated for by making the switching frequency during the step-down operation lower than the switching frequency during the step-up operation.

Abstract: An LED drive circuit is an LED dive circuit that receives an alternating voltage to drive an LED, and includes a current remove portion that removes a current from a current supply line that supplies an LED drive current to the LED. If an input current to the LED drive circuit is an unnecessary current, the LED does not light because of current removal by the current remove portion. If the input current to the LED drive circuit turns into the LED drive current from the unnecessary current, the current remove portion decreases the amount of current removed.

Abstract: A bi-directional DC-DC converter uses a transformer for both step-down and step-up operations. A switching frequency for operating a switching device is set separately for the step-down and step-up operations. When, for example, the switching frequency during the step-up operation is lower than the switching frequency during the step-down operation, the range in which the duty ratio in PWM control can be controlled is widened, compensating for step-up ratio insufficiency. Conversely, step-down ratio insufficiency is compensated for by making the switching frequency during the step-down operation lower than the switching frequency during the step-up operation.

Abstract: To provide a power supply apparatus having high control resolution of an output power. A PWM signal generating circuit includes: a non-inverting element 31, and an inverting element 32; and further includes a counter 11 for performing count operation in response to rising of a clock signal, a counter 12 for performing count operation in response to falling of the clock signal, comparison circuits 21, 22, and a multiplexer 20. These circuit elements are controlled by PWM control means 10. As another circuit element, the PWM signal generating circuit includes a logical sum element 33. The PWM signal generating circuit serves to arbitrarily change both period and logic “H” time of a PWM signal to be outputted at a time interval which is one half of the clock period. Thus, there is provided a power supply apparatus in which resolution of a PWM signal has been improved within a broad duty range, and fine control of an output power has been performed within a broad output power range.

Abstract: A small and efficient DC-DC converter is provided. In this DC-DC converter, passive elements such as an inductor and a capacitor can be reduced in size by reducing switching loss by a soft switching technology and increasing the drive frequency of a switching element. The DC-DC converter has a main switching element, a main diode and an auxiliary circuit that discharges the electric charges of the capacitance between the ends of the main switching element. The DC-DC converter includes an auxiliary inductor magnetically coupled with the main inductor, an auxiliary switching element that stores energy in the auxiliary inductor, and an auxiliary diode that discharges energy stored in the auxiliary inductor to the direct-current power source or the output side. The auxiliary inductor is coupled with the main inductor in the direction in which backward voltage is applied to the auxiliary diode when the main inductor discharges energy.

Abstract: Disclosed is a small-size, high-efficiency, isolated, bidirectional DC-DC converter. The bidirectional DC-DC converter includes a transformer in which windings are magnetically coupled, switching circuits, a diode which is connected in parallel with a switch, smoothing capacitors, and a control section. First and second DC power supplies, which are connected in parallel with the smoothing capacitors, respectively, provide bidirectional electrical power transfer. When electrical power is to be transferred from the first DC power supply to the second DC power supply, the switch is maintained in the ON state. When, on the other hand, electrical power is to be transferred from the second DC power supply to the first DC power supply, the switch is maintained in the OFF state to prevent a reverse electrical power flow from the first DC power supply.

Abstract: An LED drive circuit that drives an LED is provided with: a rectifying circuit that converts an alternating voltage into a pulsating current; a constant current circuit; and an over-temperature protection portion that limits an output of the constant current circuit, wherein the LED and the constant current circuit are connected in series on an output side of the rectifying circuit.

Abstract: The DC-DC converter connects a first and a second switching circuit for converting power mutually between direct current and alternating current respectively to a first DC power source and a second DC power source and has a transformer between the AC terminals thereof. Here, between the AC terminals of the second switching circuit and the negative pole terminal of the DC power source, a voltage clamp circuit composed of a series unit of switching devices with a reverse parallel diode and a clamp condenser is connected. An isolated bidirectional DC-DC converter which prevents a reduction in a circulating current at time of buck and an occurrence of a surge voltage at time of voltage boost and realizes highly efficiency, low noise, and miniaturization is provided.