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:
Dec. 20, 1988
Filed:
Nov. 17, 1987
David M Thomas, Tucson, AZ (US);
Rodney T Burt, Tucson, AZ (US);
Robert M Stitt, II, Tucson, AZ (US);
Burr-Brown Corporation, Tucson, AZ (US);
Abstract
A two-terminal temperature-compensated current source includes a first transistor having its emitter connected to a first terminal, its base connected to the base of a second transistor, and its collector coupled to a current mirror. The second transistor has its emitter coupled to the first terminal by a first resistor and its collector coupled to the current mirror. A second resistor is coupled between the first terminal and the base of the first transistor. The current mirror is coupled between a second terminal and the collectors of the first and second transistors so that all current supplied to the current mirror from the second terminal flows into the collectors of the first and second transistors. A third transistor has its base coupled to the collector of the first transistor, its emitter coupled to the base of the first transistor, and its collector coupled to the second terminal. The current in the first resistor has a positive temperature coefficient, and the current in the second resistor has a negative temperature coefficient. The temperature coefficient of the total current flowing between the first and second terminals is adjusted by adjusting the ratio between the first and second resistors.