| 摘要 |
PURPOSE:To provide an amplifier with a protecting function which protects the amplifier of a BTL system from a destruction due to the short-circuit of the output terminal with one power source or the other power source. CONSTITUTION:Resistors 7 and 8 are serially connected between an output terminal 4 of an inverting amplifier 2 of an amplifying part 1 and an output terminal 5 of a non-inverting amplifier 3, and the bases of transistors 9 and 11 are connected with the connecting point of the resistors 7 and 8. Then, the emitter of a transistor 10 is connected with the emitter of the transistor 9, the emitter of a transistor 12 is connected with the emitter of the transistor 11, and a reference voltage 13 is connected with the bases of the transistors 10 and 12. Then, the base of a transistor 14 is connected with the correcters of the transistors 10 and 11, the emitter of the transistor 14 is grounded, the collector of the transistor 14 is connected with a mute circuit 16, and the mute circuit 16 is connected with the inverting amplifier 2 and the non-inverting amplifier 3. |
