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. 25, 1997
Filed:
Dec. 09, 1994
Marco Corsi, Dallas, TX (US);
Gabriel A Rincon, Margate, FL (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A circuit and method for sensing and limiting current. An output driving transistor (M1) is coupled between a circuit output terminal and a power supply terminal. A replicator circuit is formed in a cross-coupled quad configuration from bipolar transistors (Q11, Q12, Q13 and Q14) and is coupled to a second transistor (M2) which generals a voltage proportional to the current flowing in the output driving transistor (M1). The current sensing circuit generates an output current which is proportional to the current flowing in the output driving transistor multiplied by a ratio of the sizes of the second transistor and the output driving transistor. In a current limiting configuration, the output of the cross-coupled quad is used to reset a flip-flop (FF1) that drives the gate terminal of the output transistor (M1), thus shutting down the output transistor before it is damaged due to excess current. The circuitry of the invention may be applied to a high side driver or a low side driver output circuit. Other embodiments are also described.