How can I distinguish between a composite tube and a two stage amplifier?
A composite tube is a system in which more than two electrode systems are arranged in the shell of an electron tube. Each electrode system is independent of the electron flow through which the individual tubes are referred to as composite tubes. A composite tube is a combination of two or more transistors in accordance with a certain law, which is equivalent to a triode, and the compound tube is also called a Darlington tube.
Two stage amplifier circuit: the basic structure of the COMS two stage Miller compensation operational transconductance amplifier is shown. It mainly consists of four parts: the first input stage amplifier circuit, the second stage amplifier circuit, the bias circuit and the phase compensation circuit.Amplifier circuit can be a weak AC small signal (superimposed on the DC operating point), by means of a device (as the core of the transistor, field effect transistor), a waveform similarity (distortion), but the output AC signal amplitude has a lot of. The actual amplifying circuit is usually composed of a signal source, an amplifier and a load composed of a transistor.
The biggest difference between the two lies:Two stage amplifying circuit, the collector circuit of the two triode is independent; and the two triode of the compound tube has two pins which are directly connected together. In the circuit, the two transistors of the composite tube show only three electrodes of E, B and C to the circuit.
