| 摘要 |
An audio amplifier circuit has a first cascode stage configured as a voltage gain stage and having an input for an audio signal, and an output. The circuit has a second cascode stage configured as a unity gain or near unity gain stage and having an input to receive an output from the first cascode stage, and a low impedance output to drive an output stage of an audio power amplifier. The first cascode stage has a first, input transistor having an input biased to a predetermined bias voltage, and a second, output transistor arranged to drive the second cascode stage. The first, input transistor of the first cascode stage may have a common-emitter configuration, and the second, output transistor may have a common-base configuration. The invention extends to an audio amplifier which includes a circuit of the invention. |
