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Machine translation
1. (WO1979000362) SEMICONDUCTOR POWER AMPLIFIER CIRCUIT
Latest bibliographic data on file with the International Bureau   

Pub. No.:    WO/1979/000362    International Application No.:    PCT/JP1978/000046
Publication Date: 28.06.1979 International Filing Date: 08.12.1978
IPC:
H03F 1/52 (2006.01), H03F 3/30 (2006.01)
Applicants:
Inventors:
Priority Data:
77/148371 09.12.1977 JP
Title (EN) SEMICONDUCTOR POWER AMPLIFIER CIRCUIT
(FR) CIRCUIT D"AMPLIFICATEUR DE PUISSANCE A SEMI-CONDUCTEURS
Abstract: front page image
(EN)In order to prevent the breakdown of an output transistor whenever an output of a single-ended push-pull type power amplifier circuit is earthed and so on, a base and an emitter of a current an detective transistor (Q28), of the same conductive type as the electrically protected transistor (Q29), are connected to a base and a emitter of the transistor (Q29) respectively. A collector current of the current detecting transistor (Q28) is supplied to a current-voltage conversion means (R27, D25) through a current mirror circuit (D24, Q24). A comparison transistor (Q25) compares a voltage of the current-voltage conversion means (R27, D25) with the output terminal (b"), so that the supply of the base current to the electrically protected transistor (Q29) is stopped by the output of this comparison transistor (Q25).
(FR)Afin de prevenir la rupture d"un transistor de sortie lorsque la sortie d"un amplificateur de puissance a sortie differentielle est mise a la masse, on connecte une base et un emetteur d"un transistor de detection de courant (Q28), du meme type que celui du transistor protege (Q29), a une base et a un emetteur du transistor (Q29), respectivement. Un moyen de conversion courant-tension (R27, D25) est alimente en courant de collecteur du transistor de detection de courant (Q28) par l"intermediaire d"un circuit de reflexion (D24, Q24). Un transistor de comparaison (Q25) compare la tension du moyen de conversion courant-tension (R27, D27) avec la borne de sortie (b"), de sorte que l"alimentation du transistor protege (Q29) en courant de base soit stoppee par la sortie de ce transistor de comparaison (Q25).
Designated States:
Publication Language: Japanese (JA)
Filing Language: Japanese (JA)