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:
Aug. 28, 2001
Filed:
Sep. 02, 1999
Ha Chu Vu, San Jose, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A driver circuit in accordance with the present invention combines current controlled current source and sink circuits, which are independent of process, temperature, and supply voltage, and voltage controlled current source and sink circuits to control the slew rate at the output of the driver circuit and thereby reduce switching noise. The driver includes an output transistor coupled to an output node, a current source, a current mirror transistor having a control node connected to the control node of the output transistor and a conduction path coupled to the current source, and a voltage controlled switch coupled between the conduction path of the current mirror transistor and the control node of the output transistor. The voltage controlled switch is coupled to the output node and is open when the output node is within a first voltage range, and is closed when the output node is within a second voltage range.