• BME 210
  • Handout 4: Superposition and Source Transform

    An algorithm for using Thevenin’s Theorem

    1. Given any linear circuit, rearrange it in the form of two networks, A and B, connected by two wires. We will simplify A and leave B alone.
    2. Disconnect network B. Define a voltage \(V_\mathrm{oc}\) (open circuit) as the voltage now appearing across the terminals of network A. Calculate \(V_\mathrm{oc}\).
    3. Turn off or “zero out” every independent source in network A to form an inactive network. Leave dependent sources unchanged. Solve for \(R_\mathrm{th}\) if you have no dependent sources.
    4. Connect an independent voltage source with value \(V_\mathrm{oc}\) in series with the inactive network. Do not complete the circuit; leave the two terminals disconnected.
    5. Connect network B to the terminals of the new network A. All currents and voltages in B will remain unchanged.

    Comments about Thevenin

    An algorithm for using Norton’s Theorem

    1. Given any linear circuit, rearrange it in the form of two networks, A and B, connected by two wires.
    2. Disconnect network B, and short the terminals of A. Define a current \(I_\mathrm{sc}\) as the current now flowing through the shorted terminals of network A. Calculate \(I_\mathrm{sc}\).
    3. Turn off or “zero out” every independent source in network A to form an inactive network. Leave dependent sources unchanged. Solve for \(R_\mathrm{th}\) if you have no dependent sources.
    4. Connect an independent current source with value \(I_\mathrm{sc}\) in parallel with the inactive network. Do not complete the circuit; leave the two terminals disconnected.
    5. Connect network B to the terminals of the new network A. All currents and voltages in B will remain unchanged.




    Last updated:
    January 6, 2018