1 DIODE CIRCUITS

diode/twodiode.m: hspice/diode.sp

id1 + ir - ii

id2 - ir

The first example that was worked on was from Figure 1. It consists of two diodes and a resistor. The main program was called "5.1_diode/twodiode.m" and at the time everything except the evaluation of the black box currents was done in this file. The program ran exactly as it was supposed to. The results were identical to that in Fig 12.1.2 of the text "Computer Methods for Circuit Analysis and Design" and are recorded in Table 1.

Rinit is the number of initalization

h is the number of init to op point itterations

i is the initialization point itterations

j is transient itterations(includes op itter h)

k is number of transient points

*******diode/twodiode.m:****************

    analysis      time      # points  tot. iter  conv.ite

    op point          0.01         1         6

    readin            0.01

    errchk            0.01

    setup             0.00

    output            0.00

          total cpu time          0.02 seconds

   node    =voltage      node    =voltage

+0:1       =  17.1178m 0:2       = 414.1113u

v_init =

     0     0     0     0     0     0

v_op =

   1.7119e-02   4.1418e-04

h =

     8

op_time =

    0.0493

optrans_time =

    0.0493

j =

     8

k =

     1

v0 =

   1.7119e-02   4.1418e-04

tic

format short

diff=1;

h=0;

v(1)=0.1;

v(2)=0.1;

while abs(diff)>0.000001

vd1=v(1);%we know

vd2=v(2);

vr=v(1)-v(2);

%we can setup.

%f1 and f2 should be made seperate funtions in terms of v1 and v2

f=[-(diode(vd1)+resistor(vr,1)-1),-(diode(vd2)-resistor(vr,1))];

%we can derive

v1e=v(1)+eps;

v2e=v(2)+eps;

%we alter

vd1=v1e;

vd2=v(2);

vr=v1e-v(2);

m=[(diode(vd1)+resistor(vr,1)-1+f(1))/eps; (diode(vd2)-resistor(vr,1)+f(2))/eps];

%we alter again

vd1=v(1);

vd2=v2e;

vr=v(1)-v2e;

mnew=[(diode(vd1)+resistor(vr,1)-1+f(1))/eps;(diode(vd2)-resistor(vr,1)+f(2))/eps];

f=f';

m=[m,mnew];

dv=lusolve(m,f);%from winter term

diff=(dv(1)^2+dv(2)^2)^0.5;

v(1)=v(1)+dv(1);

v(2)=v(2)+dv(2);

h=h+1;

%v

end

toc

format short e

v

h

format compact