Hitachi, Ltd.

Shigeo Oomae

Hideho Yamamura

Naoki Maru

Koji Nisisu

Kazunori Nakajima

Tatsuya Saito

Takashige Baba

Masayoshi Yagyu

This invention prevents a deterioration of efficiency of a power supply apparatus due to a semiconductor power supply voltage drop, prevents an increase in wasted power, and prevents erroneous operations due to feeder wire voltage drop. In the mounting structure of electronic circuits having a plurality of busbars as current paths on a printed circuit board, the plurality of busbars have almost parallel portions spaced a predetermined distance apart; a span of the parallel portions of the plurality of busbars is greater than the predetermined distance; and in the parallel portions of the plurality of busbars, the plurality of busbars are connected by a wiring pattern. In the switching power supply apparatus built on a printed circuit board, with its output voltage of less than 2 V and its output current of more than 100 A, a means is provided for making the power efficiency higher than 70%.

Electronic circuit structure, power supply apparatus, power supply system, and electronic apparatus

A signal communication apparatus of a clock reproduction system in which clock signals are extracted from each of parallel data signals for redigitizing each of the data signals. The apparatus includes a reference clock signal generating circuit which is comprised of a clock extraction circuit for extracting a clock signal from each of a plurality of bits of received data signals, and a clock signal selection circuit for selecting one of the extracted clock signals. Alternatively, the reference clock signal generating circuit may be comprised of a data signal selection circuit for selecting one of a plurality of received data signals, and a clock extraction circuit for extracting a clock signal from the selected bit. Based on the resultant reference clock signal, clock signals are obtained that are phase-adjusted for redigitizing each bit of the received data signals. The selection made in the selection circuit is switched on the basis of the output of a clock signal monitoring circuit that detects the occurrence of abnormalities in the frequency of the extracted clock signal. Thus, the extraction of clock can be continued using other bits in the event of an abnormality in the bit from which the clock is being extracted.

Clock extracting fabric in a communication device

In the current detection circuit that detects the output currents of a switching power supply circuit, an improved current detection circuit makes it possible to detect the output current directions of power supplies solves the malfunction of the power supplies vibrating or diverging during changes in load state and during parallel operation, and thus implements stable operation. The direction of an output current Ican be detected by using the current detection circuitthat has multiple switching elements Sto Seach operating synchronously with an inverter circuit.

Current detection circuit, and power supply apparatus, power supply system and electronic apparatus using the current detection circuit

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Hadano, Japan

Shigeo Oomae