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:
Oct. 21, 1986
Filed:
Aug. 05, 1983
Albrecht Lang, Leinfelden-Echterdingen, DE;
Walter H Sakmann, Nufringen, DE;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A pulse-operated transistor power amplifier having reduced switching times. The interconnected base electrodes of a pair of complementary transistors (T3, T4) are connected to the collector of a prestage transistor (T1). By a resistor (R2), the base electrodes are also connected to one terminal (+V) of the operating voltage source, to which the collector of one (T4) of the two complementary transistors is also connected. The collector of the other transistor (T3) is connected to the other terminal of the operating voltage source, which is linked with the reference potential. The emitters of the complementary transistors are also connected to each other and, by a capacitor (C1), to the base of the final stage. The voltage changes occurring at the collector when the prestage is switched are transferred by one of the two complementary transistors and the capacitor (C1) to the base of the final stage transistor (T5). The switching times of this stage are reduced by base charges which are additionally supplied or withdrawn. In a further embodiment a transistor power amplifier having two series-connected complementary final stages (T 5, T6) simultaneous conduction of both final stage transistors is prevented by means of a capacitor (C3), one electrode of which is connected to the interconnected emitters of the additional complementary emitter follower for the final stage (T6) switching the reference potential, and the other electrode of which (C3) is connected by a diode (D4) to the base of the complementary final stage (T5). The two inputs (R, U) of the power amplifier are also provided with protection transistors (T10, T11) which when one input transistor (T1) becomes conductive prevent the second input transistor (T2) from becoming conductive as a result of an erroneous input signal.