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:
Jul. 26, 1977
Filed:
Sep. 24, 1975
Hiroyuki Chihara, Suwa, JA;
Kabushiki Kaisha Suwa Seikosha, Tokyo, JA;
Abstract
An electronic timepiece battery-potential detecting circuit uneffected by temperature changes is provided. The electronic timepiece includes a D.C. power source such as a battery for providing an effective potential for energizing the timekeeping circuitry and display thereof. An electronic switching circuit is provided for detecting the effective potential of the D.C. power source. The electronic switching circuit includes a first stage switching element having a control electrode coupled to the power source for detecting the effective potential thereof, and two further electrodes defining a closed current path having either a first positive or negative current temperature coefficient in response to the control electrode being referenced above a predetermined potential, the two further electrodes defining a closed current path in response to the potential detected by the control electrode being above a predetermined potential, and a second stage switching element having a control electrode coupled to one of the first stage element further electrodes for detecting the potential thereof, the second stage element including further electrodes defining a closed current path having either a positive or negative current temperature coefficient opposite from the first stage element in response to the second stage element control electrode being referenced below the predetermined potential, the two further electrodes of the second stage element defining a closed current path.