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:
Jan. 05, 1999
Filed:
Mar. 28, 1997
Katsuhiko Sasahara, Tokyo, JP;
Yuki Hashimoto, Tokyo, JP;
Abstract
An internal voltage generating circuit for generating an internal voltage VINT from an input external voltage VEXT is provided to stabilize the internal voltage. When the external voltage VEXT is less than or equal to a first boundary voltage VT1 or a second boundary voltage VT2 (>VT1), a constant voltage VINTN independent on the external voltage VEXT, which is produced by a constant voltage generator is outputted therefrom. When the external voltage VEXT is greater than or equal to the first boundary voltage VT1 or the second boundary voltage VT2, a variable voltage (>VINTN) linearly increased with an increase in VEXT, which is produced by a variable voltage generator, is outputted therefrom. When a detecting means detects that the external voltage VEXT has been increased to VT2 or higher, the characteristic of the internal voltage is switched from a constant voltage characteristic to a variable voltage characteristic. On the other hand, when the detecting means detects that the external voltage VEXT has been reduced to VT1 or lower, the characteristic of the internal voltage is changed from the variable voltage characteristic to the constant voltage characteristic.