Problem 5.7 - Thevenin Equivalent Circuit and Matched Load
*
* The circuit for this problem is from textbook Chap. 5, Problem 30.
*
* Calculate "by inspection" the Thevenin equivalent resistance
* of the circuit. REMEMBER: Independent sources are reduced to
* zero when calculating the output (Thevenin) resistance.
*
* Use a swept resistance value to determine (approximately) the
* resistance R2 that will absorb the maximum power from the circuit.
* Use PROBE to graph the load voltage and load power. Also obtain a
* graph of the currents I(R1) and I(R2) as called for in the problem.
* At what load resistance is the maximum power delivered to the load?
* NOTE: You can use the cursor function in PROBE to follow the curve
* to the maximum power point. Read resistance value in the window.
* Deduce from this resistance and the load voltage what the value of
* the Thevenin (open circuit) voltage for the circuit would be.
* You can run a "PSpice experiment" to check on your answer to the
* Thevenin voltage question.)
*
.OPT NOPAGE
V1 1 0 DC ??? ; Enter the value of voltage source V1.
G1 3 0 ??? ??? ??? ; Enter the control voltage nodes and gain.
R12 1 2 5K
R20 2 0 10K
R1 3 0 6K
R2 3 0 RLOAD 1K ; Resistance parameter multiplier = 1000.
.MODEL RLOAD RES(R=1)
.DC RES RLOAD(R) 1 12 .50 ; Resistance R2 is swept from 1K to 12K ohms
; as a result of the multiplier = 1000.
.PRINT DC V(2) V(3) I(R1) I(R2)
.PROBE
.END