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. 10, 2009
Filed:
Sep. 27, 2005
Toyoki Suzuki, Kasugai, JP;
Mitsuaki Tomida, Kasugai, JP;
Masahiro Iwamoto, Kasugai, JP;
Osamu Uno, Kasugai, JP;
Toyoki Suzuki, Kasugai, JP;
Mitsuaki Tomida, Kasugai, JP;
Masahiro Iwamoto, Kasugai, JP;
Osamu Uno, Kasugai, JP;
Fujitsu Microelectronics Limited, Tokyo, JP;
Abstract
A tolerant input circuit that functions stably regardless of fabrication differences without having to adjust the threshold value of an input circuit. The tolerant input circuit includes a step-down device configured by an N-channel MOS transistor connected between an input pad and the input circuit. Voltage from a power supply is supplied to the gate of the N-channel MOS transistor in the step-down device to decrease the voltage of a high voltage signal provided to the input pad to the voltage of the power supply or lower. The signal with decreased voltage is provided to the input circuit. The tolerant input circuit includes a back gate voltage control circuit for increasing back gate voltage of the N-channel MOS transistor in the step-down device when the input pad is provided with a high voltage signal.