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. 20, 1996
Filed:
May. 03, 1995
Hitachi, Ltd., Tokyo, JP;
Hitachi Microcomputer Engineering Ltd., Tokyo, JP;
Abstract
An external sync signal generated by a clock generation circuit inside a single-chip microcomputer is supplied to an external terminal of this chip. The external sync signal is necessary in an external expansion mode but not in a single-chip mode. Therefore, the external sync signal is supplied to the external terminal through a control gate while a suitable control signal is inputted to a control terminal of the control gate. According to this circuit construction, control can be made in such a manner that the external sync signal is not supplied to the output terminal in the single-chip mode. As a result, it becomes possible to prevent noise from entering a signal supplied to an adjacent pin through a coupling capacity between the external terminals in the single-chip mode, and to reduce consumed power of an output buffer circuit which is disposed between the control gate and the external terminals.