Murata Manufacturing Co., Ltd.

Jvc Kenwood Corporation

Naoto Sano

Shingo Kunii

Yasuyuki Morishima

Tadahiko Matsumoto

Yasuo Ohashi

Syuichi Honda

A radio communication device includes an oscillation circuit and a modulation path. The oscillation circuit is configured to perform PLL control by using a reference frequency oscillated by a reference oscillator. The modulation path is configured to modulate a reference signal outputted from the reference oscillator, by a signal of a comparison frequency as a modulation wave.

Radio communication device, oscillation circuit, and sensitivity suppression reduction method

A switching power-supply module includes circuit boards, power conversion circuit sections provided on the respective circuit boards, conductor land patterns provided with spacing therebetween along edges of the circuit boards, conductor terminals for interconnecting the conductor land patterns. The circuit boards are stacked with spacing therebetween with the corresponding conductor land patterns being aligned, and the aligned conductor land patterns are interconnected by the corresponding conductor terminals. At least one of the conductor terminals includes an interboard-connection portion for interconnecting the conductor land patterns of the circuit boards and a leg portion that extends from the interboard-connection portion in the stacking direction of the circuit boards and that defines an external-connection portion, and the other conductor terminals each function as an interboard-connection dedicated terminal for providing connection between the circuit boards.

Switching power-supply module

A part having a large height contained in a module part is placed in a first cut-off portion formed in a part-mounting substrate to be mounted. Moreover, the module part itself is placed in a second cut-off portion formed in a mother board to be mounted.

Module part and electronic device

A power supply converts a first direct-current voltage into a second direct-current voltage and outputs the second direct-current voltage. The power supply includes a reference voltage generating circuit for generating a reference voltage, a control circuit for controlling an output voltage in accordance with the reference voltage, and a short-circuit detecting circuit for performing an output short-circuit protection operation, when short circuiting occurs at the output, by detecting the occurrence of short circuiting and by decreasing the reference voltage so that the output voltage is decreased.

Power supply, electronic device using the same, and output

A multi-output DC-DC converter includes a step-down DC-DC converter circuit which includes a switching device for switching an input DC voltage to convert it to a pulse voltage, a choke coil and a smoothing capacitor for smoothing the pulse voltage to obtain a first output lower than the input DC voltage, and a flywheel rectifying device for causing a current to flow through the choke coil when the switching device is off; and a rectifying circuit for processing and rectifying the pulse voltage in the DC-DC converter circuit to obtain a second output. Since the flywheel rectifying device is a bi-directional synchronous rectifying device which is turned on when the switching device is off, even when the load current of the first output decreases, the amplitude of the source voltage of the switching device is not reduced. Therefore, the second output obtained from the rectifying circuit always maintains a normal value.

Multi-output DC-DC converter and electronic apparatus using the same

A DC-to-DC converter is provided with an astable multivibrator containing a first time constant circuit for setting an ON period of an output and a second time constant circuit for setting an OFF period of the output, and provided with a switching element controlled by the output. The output voltage is controlled by changing the duty ratio of the astable multivibrator in accordance with the output voltage.

DC-to-DC converter and electronic device using the same

A switching power supply which is capable of generating several different output voltages and which can be easily miniaturized by using a transformer with a small number of terminals. For example, using a transformer with four terminals and three windings that are connected in series, a rectifying-smoothing circuit having a diode and a capacitor is connected to a connection point of the collector of a switching transistor and the windings. A further pair of rectifying-smoothing circuits having diodes and capacitors is commonly connected to one end of the windings, according to one example. As a result thereof, three voltages are generated.

Growing community of inventors

Otsu, Japan

Naoto Sano