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:
Apr. 17, 2012
Filed:
May. 15, 2009
Hiroyuki Nakamura, Atsugi, JP;
Hiroyuki Nakamura, Atsugi, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A surge protection circuit comprises a surge detection circuitfor detecting a surge applied to a semiconductor integrated circuit, and a protection elementfor absorbing the surge. The protection element is connected between a signal terminal for supplying a signal to the semiconductor integrated circuit and a power source terminal for supplying a power source voltage. When the power source voltage is not larger than a voltage enough to normally operate the semiconductor integrated circuit and the surge detection circuit does not detect the surge, the protection element is set in a current limiting state. When the power source voltage is not larger than a voltage enough to normally operate the semiconductor integrated circuit and the surge detection circuit detects the surge, the protection element is set in a current non-limiting state.