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:
Feb. 22, 2000
Filed:
Oct. 15, 1996
Takesada Akiba, Tachikawa, JP;
Goro Kitsukawa, Hinode-machi, JP;
Hiroshi Otori, Ome, JP;
Masayuki Nakamura, Ome, JP;
Hideo Sunami, Hinode-machi, JP;
Adin Hyslop, Dallas, TX (US);
Hitachi Ltd, of Japan, Tokyo, JP;
Abstract
An apparatus and method for a logic circuit that advantageously adapts to different operating voltages. In a preferred embodiment, a logic circuit of the present invention is implemented to drive a large capacitive load and includes a first driver, comprising a set of small, low-current drive transistors, a second driver, comprising a set of large, high-speed transistors, and an additional transistor connected between the two drivers. The additional transistor can be selectively enabled to speed up the operation of the logic circuit, and disabled to reduce the peak current of the logic circuit. The additional transistor is enabled by a voltage detection signal, which is active when the operating voltage of the chip is at a low level and inactive when the operating voltage of the chip is at a high level.