Design of negative feedback amplifier configurations#
Application of negative feedback#
Amplifiers: application of negative feedback
Negative (corrective) feedback can be regarded as a powerful design technique. It trades power gain for quality improvement and facilitates orthogonal design of the different performance aspects.
Presentation
The presentation "Amplifiers: application of negative feedback"shows that accurate, low-noise and power-efficient amplifiers can be realized through application of negative feedback.
Presentation in parts
Amplifiers: application of negative feedback (parts)
Videos
Study
Chapter 7.1
Feedback amplifiers: orthogonal design sequence
In electronic information processing systems, amplification is one of the most important basic functions. Since the basic amplification mechanism, as it is found in biased ‘active’ devices, suffers from many imperfections, negative feedback is often exploited as powerful error reduction technique.
The application of negative feedback, together with proper sequencing of the design of various performance aspects makes it possible to prevent or minimize design iterations and have an early awareness of possible show-stoppers.
Presentation
The presentation "Design of application-specific negative feedback amplifiers with operational amplifiers" gives the outline of the design sequence of high-performance negative feedback amplifiers.
Presentation in parts
Design of application-specific negative feedback amplifiers with operational amplifiers (parts)
Video
Design of amplifier types#
Amplifiers: design procedure feedback configurations
The design of negative amplifier configurations follows a strict procedure based on sensing and comparison techniques.
Presentation
The presentation "Feedback amplifiers: design procedure" illustrates the procedure for the design of a negative-feedback amplifier that accurately relates the desired electrical quantity at the load of the amplifier to that of the signal source.
Presentation in parts
Feedback amplifiers: design procedure (parts)
Video
EE3C11 lecture 7 Feedback amplifiers design procedure
Study
Chapter 7.2
Amplifiers: design of single-loop feedback configurations
Sensing of the load quantity and nullification of the difference between the feedback quantity with the source quantity form the basis of the design procedure of negative feedback amplifiers.
Presentation
The presentation "Design of Single-loop Negative Feedback Amplifier Configurations" illustrates the application of the design procedure for negative feedback amplifiers to the design of single-loop negative feedback amplifiers:
The voltage amplifier
The transadmittance amplifier
The transimpedance amplifier
The current amplifier
It illustrates a number conflicts between design aspects for passive feedback amplifiers:
Amplifier type
Sign of the transfer
Port isolation
Presentation in parts
Design of Single-loop Negative Feedback Amplifier Configurations (parts)
Video
Amplifiers design of single-loop feedback configurations (11:41)
Study
Chapter 7.2
Feedback amplifiers: ideal gain
The conceptual design or functional design of negative feedback amplifiers comprises the design of the feedback networks and their interconnection with the source, the load and nullors (ideal controllers).
Presentation
The presentation "Negative Feedback Amplifier Configurations: Ideal Gain and Controller" gives a definition of the gain of negative feedback amplifiers that have ideal controllers (nullors). The implications of controller imperfections will be discussed at a later stage.
Presentation in parts
Negative Feedback Amplifier Configurations: Ideal Gain and Controller (parts)
Video
Negative Feedback Amplifier Configurations Ideal Gain and Controller (3:35)
Study
Chapter 7.3
Amplifiers: multiple-loop feedback configurations
Each transmission-1 two-port parameter of an amplifier can be given an accurate nonzero value with the aid of a feedback network around a high-gain controller.
Presentation
The presentation "Design of Multi-loop Negative Feedback Amplifier Configurations" briefly discusses the design of multiple-loop negative feedback amplifiers.
Presentation in parts
Design of Multi-loop Negative Feedback Amplifier Configurations (parts)
Video
Amplifiers multiple-loop feedback configurations (2:58)
Study
Chapter 7.3, 7.4.1
Noise performance of negative feedback amplifiers#
Noise performance of feedback amplifiers
In general, insertion of impedances in series and/or in parallel with the signal path should be avoided. They increase:
Energy storage and power losses
Noise
Presentation
The presentation "Influence of Feedback Networks on Noise Performance of Negative Feedback Amplifiers" shows that detrimental effects caused by impedances in the feedback networks can be kept low.
Presentation in parts
Influence of Feedback Networks on Noise Performance of Negative Feedback Amplifiers (parts)
Video
Noise behavior of negative feedback amplifiers (19:42)
Study
Chapter 7.4, 7.5
Exercises
Downloads#
The presentations are summarized on the poster: "Application of Negative Feedback"
Determination of show-stopper values of controller noise sources with SLiCAP