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:
Apr. 19, 1988
Filed:
Jun. 01, 1987
Robert G Thomson, Tempe, AZ (US);
GTE Communication Systems Corporation, Phoenix, AZ (US);
Abstract
A Current Reference for providing a feedback signal to a current driver in a current-series, feedback-controlled current source circuit that includes at least one, but more likely more than one, controlled current source. The Current Reference comprises a current mirror having an input transistor coupled to an output transistor in a current mirror configuration. The input transistor of the current mirror is driven by a constant current source, Icc, so that the current mirror output transistor causes a current substantially equal to Icc to flow out of a summing node. A sensing transistor is coupled to a controlled current source for providing a current into the summing node that is representative of the current delivered by the controlled current source. As a result, the current flowing away from the summing node and into a phase inverter is representative of the difference between the delivered current and Icc. The output of the phase inverter is coupled to the current driver so as to maintain the magnitude of the delivered current at the intended value.