Sharp Kabushiki Kaisha Corporation

Katoh Electrical Machinery Company, Ltd.

Tsutomu Satoh

Atsushi Kanamori

Hirohisa Warita

Katsumi Inaba

Hirofumi Akiyama

In order to provide a hinge device exhibiting a latchless function even if a lock mechanism exposed on respective surfaces of a main body and a lid body is abolished and a small-sized electronic equipment using the same, the present invention is a hinge device coupling the main body and the lid body in a turnable manner in an open/close direction and a direction perpendicular to it, in which the hinge device includes a mounting member and supporting member to be mounted to either the main body or the lid body; a horizontal shaft member mounted to the mounting member and having a locking groove at an outer periphery thereof; an orthogonal shaft member mounted to the supporting member and having an engaging groove at an outer periphery thereof, the orthogonal shaft groove being orthogonal to the horizontal shaft member; a bracket member mounted to the horizontal shaft member and the orthogonal shaft member to allow the main body and the lid body to turn in the open/close direction and the direction perpendicular to it; and a restriction mechanism having a restriction pin being engaged with either the locking groove or the engaging groove.

Hinge device and electronic equipment using the same

In a switching power supply circuit, completion of discharging of a capacitance provided in a soft-start circuit requires a period longer than a cycle with which an activating/deactivating portion switches switching control operation of a driving portion (which performs switching control to turn on/off a switching device provided in a stepping-up DC-DC converter) between an activated state and a deactivated state. Moreover, the soft-start circuit is prevented from performing soft-start operation until discharging of the capacitance is completed. Furthermore, the activating/deactivating portion prevents the switching control operation of the driving portion from being switched from the deactivated state to the activated state from a time point that constant voltage feeding operation of a constant voltage portion (which feeds, to a comparing portion that sends an output signal to the driving portion, a constant voltage as the drive voltage) is switched from the deactivated state to the activated state until a predetermined period elapses.

Switching power supply circuit and electronic apparatus provided therewith

The voltage booster type switching power supply circuit is provided with a drive circuit for controlling a switching element, a start/stop circuit for turning the drive circuit on and off according to a brightness control signal for adjusting a brightness of a light source of a liquid crystal display device, an output voltage detection circuit for detecting whether the output voltage is greater than a predetermined voltage and feeding out a result as a comparison result signal, and a soft-start circuit that does not operate when the comparison result signal is active on the rising edge of the brightness control signal, and that operates so as to increase the output voltage gradually when the comparison result signal is inactive on the rising edge of the brightness control signal.

Power supply circuit having soft start

To permit a switched-capacitor-type stabilized power supply device to operate stably until the battery power falls considerably low, it needs to be provided with a voltage step-up circuit with a high voltage step-up factor. However, inconveniently, in a conventional switched-capacitor-type stabilized power supply device, increasing the voltage step-up factor of the voltage step-up circuit increases the difference between the voltage stepped-up by the voltage step-up circuit when the battery voltage is still high and the set output voltage, and thus lowers power conversion efficiency. By contrast, a switched-capacitor-type stabilized power supply device of the invention has a plurality of voltage step-up circuits each having a different voltage step-up factor, a switching circuit for connecting and disconnecting an input terminal, to which a direct-current voltage is applied, to and from the voltage step-up circuits, and a switching control circuit for controlling the switching circuit according to the input level to and/or the output level from the switched-capacitor-type stabilized power supply device.

Growing community of inventors

Yamatotakada, Japan

Tsutomu Satoh