Problem 4.7 - DC Node Voltage Analysis with Mixed Sources and Supernode
*
* The circuit for this problem is from textbook Chap. 4, Problem 12.
*
* Calculate the branch currents I(R15) and I(R34) with PSpice.
* Examine "by inspection" the effect of resistances connected
* to supernode terminals. That is, note that the node voltage V(4)
* is fixed because of series connection of VS1 and VS2. Estimate the
* current through R40, R45, and R50 before running the program.
*
* Perform a "PSpice experiment" to determine the effect of the
* resistances noted above. See if you can always predict the currents.
*
* PRESS "INSERT" KEY ONCE TO GO INTO "OVERSTRIKE" MODE
* IF USING THE CONTROL SHELL EDITOR. IT SAVES "DELETES."
*
.OPT nopage
IS1 0 1 DC ??? ; Enter value of current source.
IS2 ; Enter device statement for IS2.
VS1 5 4 DC 10
VS2 5 0 DC 50
VSN 6 1 DC 0 ; Add a new node 6 to the right of R15.
; Connect a current-measuring voltage
; source between node 6 and node 1.
; Note the polarity of the new source.
?S1 3 2 VSN 10 ; Enter type letter for CCVS.
R10 1 0 2
R12 1 2 5
R20 2 0 2
R30 3 0 10
R34 3 4 1
R40 4 0 ??? ; Enter resistance values for R40, R45,
R45 4 5 ??? ; and R50 from the circuit diagram.
R50 5 0 ??? ; Modify values of R40, R45, R50 at least
; twice to explore the effect of supernode.
R15 5 6 40
.DC VS1 10 10 1
.OP ; Print out the node voltages
.PRINT DC I(R34) I(R15)
.END