ECE 110/Spring 2025/Test 2

This page contains the list of topics for ECE 110 Test 2. Post questions or requests for clarification to Ed. Note - for Spring 2025, there are two changes from some previous semesters:

• Digital Logic has moved from the start to the end of the semester, so some topics have moved back (and digital logic is not on test 2)
• Op-Amps moved from the end to the middle of the semester, so some topics have moved forward (and op-amps are on test 2

Keep that in mind when looking at previous tests. The test will cover material through Homework 7 and Lecture 16.

Test II Spring 2025 Coverage

While the test is necessarily cumulative, the focus will be on the topics below.

1. Superposition - be able to efficiently solve circuit problems by using superposition.
   • In life, remember that dependent sources must be included in the different subdivisions of a superposition problem regardless of the independent source or sources you leave on. On the test however, the superposition problem will not have a dependent source.
2. Thévenin and Norton Equivalent Circuits - be able to solve for the source and resistance of a Thévenin or Norton Equivalent Circuit for a circuit comprised of resistors and 0 or more each of independent and dependent sources. Be able to draw both Thévenin and Norton Equivalent Circuits. Be able to use Thévenin and Norton Equivalent Circuits to determine the maximum power delivered to a load and the required resistance of that load to receive the maximum power. Remember that if there are controlled sources requiring unknown currents or voltages to be solved, those currents or voltages may be different when finding $$v_{oc}$$ versus $$i_{sc}$$.
3. Operational Amplifiers
   1. Know how to draw the model we are using for an operational amplifier ($$r_i$$, $$r_o$$, and a VCCS $$A(v^+-v^-))$$.
   2. Know the ideal op amp assumptions ($$A\rightarrow\infty, r_i\rightarrow\infty, r_o\rightarrow 0$$)
   3. Know the assertions we can make for idea op amps with a resistor connected between the output and the inverting input ($$v^+=v^-$$, $$i_{in}^-=i_{in}^+=0$$) and also remember that the output current for the op amp will generally not be 0 A.
   4. Be able to recognize common op amp configurations (buffer, non-inverting amp, inverting amp, summation amp, difference amp).
   5. Be able to analyze op amp circuits using NVM and be able to determine powers delivered by sources or absorbed by resistors in the circuit.
   6. Be able to build circuits that are modular or that require no current from a source by using buffer amps
   7. Be able to build a circuit with op amps to represent a linear algebra experssion
4. Reactive elements (Capacitors and Inductors)
   1. Know the main model equation relating voltage and current and what it means for the voltage across a capacitor or the current through an inductor
5. Be able to find equivalent capacitance for a network of capacitors and equivalent inductance for a network of inductors
   1. Know the equation for energy stored in a capacitor or an inductor. Note that if you use superposition to find the capacitor voltage or inductor current, you must wait until the end of the superposition process, when you have the total voltage or current, to find the energy stored.
   2. Be able to represent a circuit with reactive elements in the DC Steady State
   3. Be able to determine a model equation for circuits comprised of R, C, and sources or R, L, and sources
6. DC Switched circuits / constant source circuits
   1. Determine conditions just before something changes, just after something changes, and as time goes to infinity given piecewise constant forcing functions
   2. Set up and solve a first-order differential equation with initial conditions and constant forcing functions
   3. Accurately sketch the solution to switched circuit / constant source circuit

Specifically Not On The Test

1. Complex numbers
2. Sinusoids / ACSS
3. Phasors