ECE 595 Assignment 3

Extend your matlab circuit analysis program to handle diodes. The diode characteristic equation is given by

where I_S = 1e-14 and V_T = 0.025 V.

Your program should plot the current through the diode and the norm of the solution step size as a function of iteration.

Solve the following problems:

1. solve for diode voltage given diode current:

   D D1 1 0  0
   I I1 0 1 .01
   

2. solve for diode voltage with series resistance, given current source:

   D D1 1 0  0
   R R1 2 1 100
   I I1 0 2 .01
   

3. Solve for diode voltage and current given voltage source:

   D D1 1 0  0
   R R1 2 1 100
   V V1 2 0  3
   

4. Solve for diode voltages and current (two diodes) forward biased:

   D D1 1 0  0
   D D2 2 1  0
   R R1 3 2 100
   V V1 3 0  3
   

5. Solve for diode voltages (two diodes) reverse biased:

   D D1 1 0  0
   D D2 2 1  0
   V V1 2 0 -3
   

   Explain why the analysis is nearly singular.

Maintained by John Loomis, last updated 30 Aug 2002