So why would the answer gotten from doing source transformations be different from shorting the leads? I think its because the circuit in the aforementioned problem is internally altered by the circuit attached to it, whereas if I did the same thing as done in photo 3 of the first post on this example below, then it would be the exact same answer for the original circuit and both equivalents. The current Io is dependent on input voltage Vi. The last circuit for this lab uses a Current Dependent Current Source. This output current is a scalar multiple of the input voltage. 1 For those of you using iCircuit, the symbol independent voltage source is the. So the algebra works out in doing it both ways. Voltage Controlled Current Source (VCCS): It is defined as the source whose output current depends on the voltage across some circuit element. The first and second outputs of the block are respectively the. And if you do it out using a source transformation you get the same thing, as can be seen at the bottom right, a current source of Vs/R1, with a thevenin/norton resistance of R1 || R2. The Controlled Voltage Source block provides a voltage source controlled by a Simulink signal. So I tried doing it both ways, shorting the leads, which yielded a thevenin/norton resistance of R1 and R2 in parallel, and a norton current of Vs/R1. The ratio Vin/Iin gives the Thevenin resistance viewed from the leads.īut doing source transformations/simplification after you algebraically solve for the current and calculate the voltage of the dependent source should aslo work, right?įor example this algebraic example, you need to find the norton and thevenin equivalents of the circuit shown in the top right. The other method for finding Rth is by putting a voltage source of known magnitude (usually 1V) across the output leads and calculating the current supplied by the source. When you short the output leads, the dependent source also gets shorted by means of its transfer function. Shorting the output leads is absolutely fine here as you are not "physically" disabling the dependent source. Actually, this is one of the two methods you can use when dealing with dependent sources. This video deals with a dependent source circuit, which is reduced to Norton equivalent circuit.This circuit is collected from following handout of Prof.