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:
May. 04, 1976
Filed:
Mar. 11, 1974
James R Gaskill, Jr, Pacific Palisades, CA (US);
Don C Devendorf, Los Angeles, CA (US);
Hughes Aircraft Company, Culver City, CA (US);
Abstract
Diodes having a fast response time are used in an Emitter-Coupled Logic (ECL) current switch circuit to cause the injection of an idle current in each of the transistors of said switch. The injection of the idle current through these transistors causes them to operate at all times in an active region. When the transistors remain in the active operating region and are subjected to a switching transient, the parasitic capacitance associated with emitter base and collector base junctions are not charged and discharged to the same extent that they would be if the transistor was turned off completely. Moreover, if the transistors are held on, delay required for minority profile 'buildup' in the base region is reduced and the current switch's propagation delay is reduced. When the fast response diodes are used to cause the injection of idle current in a cascode circuit, the overall transient response is greatly improved in both the lower and upper current switch sections; and there is a reduction of spurious output signals. Schottky diodes can be used in said circuit due to their fast response time. Alternatively large value resistors or current source transistors are used when diodes are not used.