Distributed emitter follower amplifier

Abstract

The invention discloses a distributed emitter follower amplifier. N stages of transistors and N bias networks use an emitter follower amplifier connection method; third ends (collectors or drains) ofeach stage of the transistors are also provided with a time-delay network; each stage of time-delay network compensates the phase of an output signal of the third end of the respective stage field-effect tube, so that the output signals of second ends of each stage of the time-delay network have the same phase, and the maximum gain can be obtained by superimposing the output signals of each stageof the transistors. The circuit structure is simplified because no base / gate artificial transmission line is existed; no base / gate absorption resistor and no collector / drain absorption resistor are existed, so that the output signal of each stage is converted into a useful signal, and the efficiency of the distributed emitter follower amplifier is improved; moreover, in the circuit structure, as the operating frequency increases, the output signals of the transistors of each stage are phase compensated, so that the final output signals have the same phase, and the high-frequency gain is improved.

Description

technical field [0001] The invention relates to the technical field of distributed amplifiers, in particular to a distributed emitter follower amplifier. Background technique [0002] The principle of the traditional distributed amplifier is to divide the large-signal active device into small devices, and use the parasitic capacitance of the inductor and the transistor to form an artificial transmission line. These transistors are cascaded through the artificial transmission line, which reduces the influence of the parasitic parameters of the transistor on the performance of the amplifier. And through these transistors, the input signal is amplified and coupled to the output transmission line through the transistor, which breaks through the limitation of the gain-bandwidth product, and can obtain a relatively large flat gain in the range of multiplication. [0003] Please refer to figure 1 , taking a bipolar transistor as an example, figure 1 It is a structural schematic d...

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Problems solved by technology

But on the one hand, it increases the complexity of the circuit structure and reduces the efficiency of the distributed amplifier; on the other hand, only half of the output signal of each transistor in the circuit structure is transmitted to the right to become a useful signal, while to the left The reverse wave is absorbed by the impedance of the base and collector, further reducing the efficiency of the distributed amplifier

In addition, as the operating frequency of the circuit increases, the loss and parasitic parameters of the artificial transmission line cannot be ignored, and the phases of the signals at the output of the transistor are no longer the same, and the maximum gain cannot be obtained after superposition

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