Eingangsverstärkerstufe

Eingangsverstärkerstufe refers to the initial stage of an electronic amplifier. Its primary function is to receive the input signal and amplify it to a level suitable for subsequent stages. This stage is critical because it determines many of the amplifier's overall characteristics, including its gain, input impedance, and noise performance. The input signal is often a very small voltage or current, and the Eingangsverstärkerstufe must be capable of amplifying this signal without introducing significant distortion or unwanted noise.

Common configurations for an Eingangsverstärkerstufe include common-emitter, common-collector, and common-base amplifier circuits in bipolar junction transistor (BJT) designs, or common-source, common-drain, and common-gate configurations for field-effect transistors (FETs). The choice of configuration depends on the desired input and output impedance, voltage or current gain, and frequency response. For instance, a common-collector or common-drain stage is often used when a high input impedance is required, which helps prevent loading down the signal source.

The performance of the Eingangsverstärkerstufe is often a limiting factor for the entire amplifier. Noise generated in this first stage is amplified by all subsequent stages, making it the dominant source of noise in the overall system. Similarly, any distortion introduced here will also be amplified. Therefore, careful design and component selection are essential for this initial amplifier stage to achieve optimal performance in terms of signal fidelity and signal-to-noise ratio.