A "back amplifier" likely refers to what is more commonly known as a feedback amplifier. This type of amplifier incorporates a signal path that runs from its output back to its input.
Understanding the Feedback Amplifier
Based on the provided reference, a feedback amplifier is defined as:
- A type of amplifier whose feedback exists between the output and input signal.
- The fundamental concept is feeding the output signal back to its input circuit. This process is called feedback, which gives the amplifier its name.
- The presence of feedback makes the amplifier's operation dependent between the output and input with effective control.
In essence, a feedback amplifier takes a portion of its output signal and combines it with the input signal. This interaction can significantly alter the amplifier's characteristics, such as its gain, bandwidth, input and output impedance, and linearity.
Why Use Feedback?
Engineers use feedback in amplifier circuits for various reasons, including:
- Improved Stability: Feedback can help stabilize the amplifier's performance against variations in components or temperature.
- Reduced Distortion: Negative feedback is particularly effective at reducing non-linear distortion introduced by the amplifier components.
- Controlled Gain: Feedback allows for precise control over the amplifier's overall gain, making it less sensitive to the intrinsic gain of the amplifier circuit itself.
- Modified Impedance: Feedback can be used to increase or decrease the input and output impedances of the amplifier circuit as required for specific applications.
While the term "back amplifier" isn't standard terminology in electronics, the description from the reference perfectly matches the definition and operation of a feedback amplifier, where a signal path goes "back" from output to input.
