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. 10, 1998
Filed:
Jan. 06, 1997
Fumio Nakajima, Tokyo, JP;
Citizen Watch Co., Ltd., Tokyo, JP;
Abstract
The electronic watch according to the invention comprises an energy source 1 (power supply), storage circuit 3, clock output unit 4, constant voltage circuit 5, voltage detection circuit 6, switching circuit 8, and control unit. The energy source 1 transforms external energy into electric energy and supplies a power supply voltage. The storage circuits 3 stores the power supply voltage or a booster voltage of the power supply voltage and thereby supplies a storage voltage. The clock output unit has a watch system and a condenser of a small capacitance, receives any of the power supply voltage or the booster voltage, and the storage voltage, and supplies a plurality of logic signals. The constant voltage circuit 5 generates a reference voltage from the clock voltage. The voltage detection circuit 6 compares the power supply voltage or booster voltage, storage voltage, and clock voltage selectively with a voltage set on the basis of the reference voltage and supplies a voltage detection signal. The switch circuit 8 is provided with a plurality of switches for controlling charging times of the storage circuit and the clock output unit. The control unit controls the switching circuit 8 by a plurality of pulse width variable switch control signals corresponding to a plurality of the logic signals and the voltage detection signal.