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. 29, 2009
Filed:
Nov. 29, 2007
Kazunori Hayami, Fukuoka, JP;
Tetsuya Ohtani, Fukuoka, JP;
Kazunori Hayami, Fukuoka, JP;
Tetsuya Ohtani, Fukuoka, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An interface circuit includes a driver circuit () made up of a combination of a plurality of transistors, a calibration circuit () for performing selection of on and off of one or more of the plurality of transistors for adjusting on-resistance thereof, and a terminating resistor () that is connected to an output side of the driver circuit (). One or more of the transistors are turned on based on an output of the calibration circuit (), so that a combination resistance value of the on-resistance and the terminating resistor matches characteristic impedance of the transmission line. The driver circuit (), the calibration circuit () and the terminating resistor () are formed on the same semiconductor integrated circuit SK, and the calibration circuit () detects process variation and temperature variation of the transistor and the resistor formed on the semiconductor integrated circuit (SK).