30-11-2023: Application of balancing techniques#
Lecture: EE4109-6
Location: Pulse Hall 4
Time: 08:45 - 10:30
Quiz#
Balancing#
Introduction to balancing
Balancing is a compensation technique. With this error reduction technique it is possible to reduce the adverse effects of reproducible errors.
Balancing techniques can be used to create odd transfer functions. By doing so, the influence of biasing errors on the static transfer of balanced amplifier stages is much less less than of unbalanced stages.
Odd transfer functions with a compressing or an expanding V-I transfer can be realized with anti-series or anti-parallel connections of unbalanced elements
Presentation
The presentation Introduction to balancing introduces the concepts of additive compensation and balancing.
Video
Balancing of two-terminal elements
Anti-series or complementary-series conection of two biased nonlinear two-terminal elements results in an element with an odd ci(v) characteristic of which the bias voltages of the two-terminal device are converted into common-mode bias voltages of the anti-series connection.
Anti-parallel or complementary-parallel connection of two biased nonlinear two-terminal elements results in an element with an odd i(v) characteristic of which the bias currents of the two-terminal device are converted into common-mode bias currents of the anti-parallel connection.
The small-signal v(i) relation, as well as the stationary noise behavior of such connections can easily be related to those of the biased two-terminal elements of which is is constituted.
Presentation
The presentation "Balancing of two-terminal elements" illustrates the application of balancing techniques using two-terminal elements only.
Video
Balancing of two-ports
Anti-series connection of two (equal) biased nonlinear two-ports or series connection of two complementary two-ports results in a two-port with an odd i(v) characteristic, and of which the bias voltages of the two-ports are converted into common-mode bias voltages of the anti-series connection.
Anti-parallel connection of two (equal) biased nonlinear two-ports, or paralell conccetion of two complementary two-ports results in a two-port with an odd i(v) characteristic, and of which the bias currents of the two-ports are converted into common-mode bias currents of the anti-parallel connection.
The small-signal v(i) relation, as well as the stationary noise behavior of such connections can easily be related to those of the biased two-ports of which it is constituted.
Presentation
The presentation "Balancing of two-ports" illustrates the application of balancing techniques using two-ports.
Video
Balancing: differential pair
The differential-pair can be considered an anti-series connection of two CS stages. By doing so, its properties can easily be related to those of the CS stage.
Presentation
The presentation "Balancing: differential pair" relates the large-signal and the small-signal static and dynamic transfer, as well as the stationary noise performance of the differential pair to the corresponding properties of the CS stage.
Download
LTspice differential pair simulation: Chapter 6.4.2.
Video
Balancing: push-pull stage
The push-pull stage can be considered a complementary-parallel connection of two CS stages. By doing so, its properties can easily be related to those of the CS stage.
Presentation
The presentation "Balancing: push-pull stage" relates the large-signal and the small-signal static and dynamic transfer, as well as the stationary noise performance of the push-pull stage to the corresponding properties of the CS stage.
Download
LTspice push-pull stage simulation: Chapter 6.4.3.
Video
Poster#
Group exercise#
Continue with the exercise from the previous lecture
If we would like to use a differential pair (anti-series connected CS stage) as input stage of A1, what would be the consequences for the design of the noise performance of the amplifier.