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. 04, 2003
Filed:
Jun. 27, 2000
Al Becker, Austin, TX (US);
Bakul Damle, Round Rock, TX (US);
National Instruments Corporation, Austin, TX (US);
Abstract
A circuit that protects a current shunt or any analog measuring circuit without the implementation of fuses. In a particular embodiment, a circuit comprises a current shunt and a plurality of transistors that may be configured to function as a fuse. One of the transistors may be deactivated once the input voltage exceeds a negative threshold voltage. The other transistor may be deactivated once the input voltage exceeds a positive threshold voltage. By deactivating the transistors once the input voltage exceeds a negative or a positive threshold voltage, the transistors are configured to function as a fuse and provide input protection for a current shunt or for any analog measuring circuit. In another particular embodiment, a circuit provides protection for a first and second current shunt where the second current shunt is less in resistance than the first current shunt. The circuit further comprises a plurality of transistors that may be configured to function as a fuse. The circuit further comprises a current limiter to protect the second current shunt at a second range and a voltage limiter to protect the current limiter at a first range, where the second range is smaller than the first range. The voltage limiter operates to deactivate the transistors once the input voltage exceeds a negative or positive voltage threshold of the first range. The current limiter operates to limit the current flowing through the transistors once the input voltage exceeds a negative or positive voltage threshold of the second range.