Protecting device for amplifier

Abstract

Abstract PURPOSE: To ensure a quick protective action to the amplifier in an extremely accurate way by controlling the protective circuit of the detector circuit which detects the fault occurring at the output circuit of the direct-coupled amplifier. CONSTITUTION: The emitter is connected to output terminal O 1 and O 2 of balanced direct-coupled amplifier PA as well as to the load of serial resistor R 13 and R 14 inserted between load L, and the fixed bias voltage is applied to the base. At the same time, transistors Q 11 ∼Q 13 are provided to produce the detection output from the collector. Diode D 11 and D 12 connected so as to be in the forward direction to the base current are connected between the transistor base and the output terminal side of R 13 and R 14 . Detector circuit DT of such constitution is provided every output terminal of amplifier PA. Then protective circuit PT is controlled by the detection output of circuit DT, thus ensuring the protective action to amplifier PA in a quick and extremely assured way. COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Kunio Seki
• 👤 Reisuke Sato
• 👤 Hiroo Adachi

Bibliographic Details