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11: Active Filters

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    Learning Objectives

    After completing this chapter, you should be able to:

    • Describe the four main types of filters.
    • Detail the advantages and disadvantages of active versus passive filters.
    • Describe the importance of filter order on the shape of a filter's response.
    • Describe the importance of filter alignment on the shape of a filter's response.
    • Compare the general gain and phase response characteristics of the popular filter alignments.
    • Analyze high- and low-pass Sallen and Key filters.
    • Analyze both low and high Q band-pass filters.
    • Analyze state-variable filters.
    • Analyze notch filters.
    • Analyze cascaded filters of high order.
    • Detail the operation of basic bass and treble audio equalizers.
    • Explain the operation of switched capacitor filters, and list their relative advantages and disadvantages compared to ordinary op amp filters.

    11: Active Filters is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by James M. Fiore via source content that was edited to conform to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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