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:
Mar. 20, 2007
Filed:
Jun. 05, 2006
Naoki Yada, Tokorozawa, JP;
Yasuyuki Saito, Higashiyamato, JP;
Yasushi Shibatsuka, Takasaki, JP;
Katsunori Koike, Hitachiota, JP;
Mitsuhiko Okutsu, Mito, JP;
Naoki Yada, Tokorozawa, JP;
Yasuyuki Saito, Higashiyamato, JP;
Yasushi Shibatsuka, Takasaki, JP;
Katsunori Koike, Hitachiota, JP;
Mitsuhiko Okutsu, Mito, JP;
Renesas Technology Corp., Tokyo, JP;
Hitachi Engineering Co., Ltd., Ibaraki, JP;
Abstract
A semiconductor integrated circuit includes a memory circuit, an oscillator circuit which generates an internal clock signal, based on control information held in the memory circuit, and a logic circuit which generates control information that causes the frequency of the internal clock signal to coincide with the frequency of an external clock signal. The internal clock signal is used for a synchronous operation of an internal circuit. Even if an error (undesired variation) occurs in the oscillation characteristic of the oscillator circuit due to process variations, it is possible to cause an internal clock signal frequency to coincide with an external clock signal frequency corresponding to a target frequency without the need for external attachment of a crystal oscillator and the input of an external clock signal.