EE331L Analog Electronics Laboratory 2

A Phase shift Oscillator


Most of you have or are currently taking “Feedback Control Systems”.  In this lab you will build an oscillator using a “Phase Shift” design and Operational amplifier(s).  The result should oscillate reliably at your designated frequency (different for each group).


  1. Design a Phase Shift Oscillator

§  Design, simulate and implement a Phase Shift Oscillator as described in the above Wikipedia article that is intended to oscillate at a specified audio frequency.

§  You may use your own design and may choose from any op amp and other components present in the teaching lab. 

§  The output signal should be a low distortion sinusoid,

§  Use an oscilloscope to capture test waveforms from your amplifier before presenting your design.

  1. Simulate and test your circuit

§  First simulate your design in BOTH MatLab and Multisim to determine that your design will perform as desired.

§  Run a Multisim Monte-Carlo simulation to determine the impact of component tolerances on your oscillator design.


Analysis and Report:

Please complete a brief lab report (2-3 pages).  Focus on explaining your design process.  Explain how you chose the overall circuit design and the key components.  Explain the important parameters and effects of your circuit, as well as how it could be improved in the future, or with more resources.  Your report should address the following:

§  Circuit diagram and derivation of all equations (not showing a derivation for your equations will result in a 2 point deduction in the lab score) used to analyze the design and or select component values. Note that the use of active buffers between phase shift sections results in a much simpler circuit to analyze.

§  Waveforms, both from simulation and physical tests.

§  Amplitude and Frequency sensitivity to component precision (again use a Monte Carlo simulation).

§  Power considerations


Your lab report is due before the lab session that follows the two sessions for this project.