ELEC 226, Spring 2003
Prof. Rich Kozick

## Laboratory 3 Introduction to Analog Filter Analysis and Design

Objective: In this lab, you will continue to build your knowledge about frequency response and analog filters. You will design analog filter circuits to meet frequency response specifications, build the circuits, and compare the measured frequency response with the analytical frequency response.

We will revisit the topics of frequency response and filter design later in the course.

Design Problems:

1. Design a first-order, low-pass filter with a passband gain of -5 volt/volt at low frequencies and a cutoff frequency of approximately 500 Hz.

2. Design a first-order, high-pass filter with a passband gain of -5 volt/volt at high frequencies and a cutoff frequency of approximately 5000 Hz.

3. Design a band-pass filter with a passband gain of -20 volt/volt, a low cutoff frequency of approximately 1000 Hz, and a high cutoff frequency of approximately 2000 Hz.

For each filter, do the following. Begin with the low-pass filter, and do as many of the other filters as you can.

• Derive the analytical expression for the magnitude of the frequency response for each filter. Explain how this formula is used to choose the circuit component values to achieve the design specification.

• Build each circuit and measure the frequency response. Be sure to measure the cutoff frequency, and compare it with the design specifications. Make (computer-generated) plots that show the analytical and measured frequency responses.