The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 03, 1992
Filed:
Mar. 20, 1992
Osamu Ikeda, Tokyo, JP;
Dia Semicon Systems Incorporated, Tokyo, JP;
Abstract
The electric power unit of the present invention for a battery-powered electronic appliance comprises a chopper-controlled nonisolated DC-DC converter for converting the output voltage of a battery into required voltage, a bypass switch for bypassing the DC-DC converter, a comparator for comparing the output voltage of the battery with a reference voltage corresponding to the required voltage of the load circuit, and a controller for controlling the bypass switch on the basis of the output signal of the comparator. When the output voltage of the battery is higher than the reference voltage, the battery is connected directly to the load circuit, so that the power of the battery can be supplied to the load circuit without loss due to the operation of the DC-DC converter. When the output voltage is lower than the reference voltage, the output voltage of the battery is converted into a voltage nearly equal to the required voltage of the load circuit by the DC-DC converter, so that substantially all the energy stored in the battery can effectively be used.