Lecture 12

color coded resistors

Overview of the program

  1. Agenda lecture 12.

  2. Discussion of the homework

    1. Design of the input stage using LTspice LTspiceInputStageNoise.zip.
    2. Design of the output stage using LTspice LTspiceOutputStageDrive.zip.
    3. Design of a single-stage solution using complementary-parallel CS stage LTspiceSingleStage.zip.
    4. SLiCAP files Active Antenna.

  3. Presentations

    Note: scrolling through presentations

    Always open presentations in a new tab: CRTL + click

    Physical breakdown of the active antenna

    Presentation

    The presentation “Active Antenna Physical Breakdown” summarizes the functions and the most relevant performance aspects of the active antenna at this stage of the design.

    Controller Design

    Presentation

    The presentation “Controller Design” discusses the stage type, the most relevant performance aspects and the design parameters of the input stage and the output stage. It also briefly motivates the use of multiple stages.

    Stages’ contribution to LP product

    Presentation

    The presentation “Contribution of Stages to LP product” discusses the contribution of various amplifier stages to the loop gain-poles product of a negative feedback amplifier.

    It also shows a way to calculate the absolute minimum number of stages in the controller of a negative feedback amplifier that are required to fullfill the bandwidth requirements of the amplifier.

    Miller Effect and Cascode Stages

    Presentation

    The presentation “Pole-splitting and Cascode stages” discusses the pole-splitting in RC-loaded CS stages. If such stages are applied in the controller of a feedback amplifier, pole-splitting may result in a reduction of the loop gain-poles product of the amplifier. Pole-splitting can be eliminated by cascading the CS stage with a current follower (e.g. CG stage). The cascade connection of the CS stage and a CG stage is usually referred to as a cascode stage.

    Study

    Chapter 5.3, Chapter 13.2.3, Chapter 14.2.6

    Preferred controller stages

    Presentation

    The presentation “Preferred Controller Stages” presents two preferred controller stages

    1. The inverting CS-CG cascode stage
    2. The noninverting CD-CG stage

    These stages show approximate unilateral behavior and maximally contribute to the LP product of a negative feedback amplifier.

Homework

  1. Design a two-stage amplifier. Use SLiCAP for the design of the bandwidth. If you simulate the loop gain, be sure you don’t select the loop gain reference inside a local loop. To this end you can set the drain-gate capacitance to zero in the stage where you select the loop gain reference.