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:
Jun. 18, 1996
Filed:
Apr. 20, 1993
Yosimitu Sibata, Okazaki, JP;
Tadao Nojiri, Oobu, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
A power supply apparatus suitable for a hand-held terminal or the like. In response to a power supply switch turning on, a voltage of a battery is supplied to a boosting voltage circuit and maintained through a diode at a charge capacitor and then applied to a memory, thereby allowing the hand-held terminal to operate normally. While the power supply switch is turned off, the supply voltage stored in the capacitor and applied to the memory is compared with a reference voltage in a comparator. When the supply voltage is lower than the reference voltage, the comparator outputs a signal to a control circuit couple the battery to the boosting circuit for a predetermined time so as to re-charge the capacitor and therefore guarantee back-up of the memory. This arrangement allows the use of the hand-held terminal for a longer time than is normally achieved concurrently with a normal operation of the hand-held device.