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. 13, 1988
Filed:
Jun. 05, 1987
Applicant:
Inventors:
Richard E Hester, Eden Prairie, MN (US);
Tuan Ngo, Minneapolis, MN (US);
Assignee:
VTC Incorporated, Bloomington, MN (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G05F / ;
U.S. Cl.
CPC ...
323315 ; 323314 ; 307297 ;
Abstract
An amplifier output stage includes current limiting circuitry for limiting the current in the output stage if the output terminal is shorted to ground. The current sinking and the current sourcing output transistors each have a current limiting circuit which mirrors the collector current of the output transistor, produces a voltage which is a function of the mirrored collector current, and controls base current to the output transistor as a function of the voltage. The output current limiting function, therefore, is provided without sacrificing output voltage swing of the output stage.