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Project Notes

#738 Active Filter Cookbook

Book notes: Active Filter Cookbook, by Don Lancaster. First published January 1, 1996.

Build

Notes

See also:

Contents

CHAPTER 1: SOME BASICS

  • Why Use Active Filters?
  • Frequency Range and Q
  • A Simple Active-Filter Circuit
  • Types of Active-Filter Circuits
  • Some Terms and Concepts
  • A Design Plan

CHAPTER 2: THE OPERATIONAL AMPLIFIER

  • A Closer Look
  • Some Op-Amp Circuits
  • Some Op-Amp Limitations
  • Which Operational Amplifier?

CHAPTER 3: FIRST AND SECOND-ORDER NETWORKS

  • Normalization and Scaling
  • First-Order Low-Pass Section
  • First-Order High-Pass Section
  • Second-Order Low-Pass Section
  • Second-Order Bandpass Section
  • Second-Order High-Pass Section
  • Other Second-Order Responses
  • K and S
  • Summing Things Up

CHAPTER 4: LOW-PASS AKD HIGH-PASS FILTER RESPONSES

  • Order
  • Selecting a Shape
  • Low-Pass Response Curves
  • High-Pass Filter Characteristics
  • How Accurate?
  • Using the Curves
  • Can We Do Better?

CHAPTER 5: BANDPASS FILTER RESPONSE

  • Some Terms
  • Selecting a Method
  • Filter-Shape Options
  • Second-Order Bandpass Filter
  • Two-Pole, Fourth-Order Bandpass Response
  • Three-Pole, Sixth-Order Bandpass Response
  • Component Tolerances and Sensitivities
  • Using This Chapter

CHAPTER 6: LOW-PASS FILTER CIRCUITS

  • Types of Low-Pass Filters
  • First-Order Low-Pass Circuits
  • Second-Order Low-Pass Circuits
  • Unity-Gain Sallen-Key Circuits
  • Equal-Component-Value Sallen-Key Circuits
  • Unity-Cain State-Variable Circuits
  • Variable-Gain State-Variable Circuits
  • The “Ripoff” Department
  • Pitfalls and Restrictions
  • Some Design Rules

CHAPTER 7: BANDPASS FILTER CIRCUITS

  • Multiple-Feedback Bandpass Circuit
  • Sallen-Key Bandpass Circuit
  • State-Variable Active Filters
  • The Biquad-Frequency Limitations
  • Some Rules
  • Ringing, Electronic Bells, and the Time Domain

CHAPTER 8: HIGH-PASS FILTER CIRCUITS

  • Some High-Pass Restrictions
  • First-Order High-Pass Circuits
  • Second-Order High-Pass Circuits
  • Another “Ripoff” Department
  • Some High-Pass Design Rules

CHAPTER 9: TUNING, VOLTAGE CONTROL, ANO ELLIPTICAL FILTERS

  • Components and Tuning
  • Manual Wide-Range Tuning
  • Voltage and Digital Control
  • Two New Techniques-A Two-Quadrant Multiplier
  • Notch Filters
  • Cauer or Elliptical Filters

CHAPTER 10: SOME APPLICATIONS-WHAT GOOD ARE ACTIVE FILTERS?

  • Brainwave Research
  • Electronic Music
  • Audio Equalizers
  • Quadrature Art
  • Oscillators and Signal Sources
  • Test and Lab Filters
  • Speech Therapy
  • Psychedelic Lighting
  • Tone Signalling
  • Modems
  • Other Applications

REFERENCES

About LEAP#738 Books

This page is a web-friendly rendering of my project notes shared in the LEAP GitHub repository.

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