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:
Aug. 12, 1997
Filed:
Jan. 27, 1995
Yasufumi Honda, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A clock apparatus has a first clock unit, a backup power supply unit, a second clock unit, and a control unit. The first clock unit is used to count time, and the backup power supply unit is used to supply a backup power voltage to the first clock unit, when a general power supply unit does not supply a general power voltage to the clock apparatus. The second clock unit has a higher accuracy than the first clock unit. The control unit is used to adjust the time counted by the first clock unit in accordance with a specific period counted at the second clock unit, and the control unit is also used to control the resetting of an operation of the second clock unit, when the general power supply unit starts to supply the general power voltage to the clock apparatus after the general power supply unit has been stopped. Consequently, the clock apparatus has a high accuracy corresponding to the second clock unit, and has a low consumption power when the general power supply unit cannot to supply the general power voltage to the clock apparatus, so that an improved batter backup operation for the clock apparatus can be realized.