Lecture 4 RC Circuits

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Lecture 4 RC Circuits
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Topics

• 1. Review homework 1
• 2. Review equivalent R circuits
• 3. Thevenin equivalent
• 4. Definition of Capacitance
• 5. Intuitive definitions
• 6. 3 functions of RC circuit
• 7. Bode Plot
• 8. solution to differential equation

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Homework 1 review

• Measurement errors for AC power
• Measurement errors for Resistance
• Trick circuit 3

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Resistive circuits

• Example of Bridge network
• Examples in next homework 2
• Pi T transform equations

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Thevenin equivalent

• Show how to make one
• Ladder network

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Definition of Capacitance

• i C dv/dt
• Give construction
• Explain E field and EM waves
• Give size and voltage ranges

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3 functions of RC circuit

• Low pass ---- high pass
• Integrator ---- differentiator
• Time delay ---- predictor

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Intuitive definitions

• RC circuit show charging
• At low frequency looks like open
• At high frequency looks like short
• Square wave in show output
• Physiological example lungs
• Physiological example heart
• Physiological example heat

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Bode Plot

• Description
• Phase plot
• Log-log
• Cutoff

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Solution to differential equation

• Get equation for RC circuit time domain
• Define step input
• Solve for homogenous solution
• Solve for particular solution
• Match boundary conditions
• Solve for time domain response