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:
Sep. 12, 2006
Filed:
Apr. 17, 2003
Nobutaka Kitagawa, Machida, JP;
Nobutaka Kitagawa, Machida, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A semiconductor circuit system has first, second, and third external terminals electrically separated from each other. The first external terminal is configured to receive a first power supply voltage in a normal operation. A protection circuit section is provided in the circuit system and includes a rectifier to allow a surge current to pass therethrough. The rectifier has a current passage connected between a specific terminal connected to a protection target and the third external terminal. The protection circuit section further includes a first PMOS transistor configured to trigger the rectifier, based on a surge voltage inputted into the second external terminal. The first PMOS transistor has a current passage connected between the second external terminal and a base of the NPN transistor. The first PMOS transistor has a gate connected to the first external terminal.