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. 14, 2006
Filed:
Jan. 17, 2003
Hung Pham Le, San Jose, CA (US);
Hung Pham Le, San Jose, CA (US);
Exar Corporation, Fremont, CA (US);
Abstract
An analog transfer gate that can be connected to an external line of a chip that is also connected to a digital circuit. The transfer gate includes both NMOS and PMOS transistors for passing the analog signals in both directions. A voltage sensing circuit is connected to the external line and is configured to sense a voltage that is higher than the supply voltage of the analog circuit. When this occurs, it produces a sense output signal. The sense output signal activates a protection enabling circuit that turns off the PMOS and NMOS transistors. In addition, at least one additional protection transistor is activated to avoid too high of a voltage being applied across any of the transistor junctions.