R1 = 100;  R2 = 100;  R3 = 20;
C = 1e-6;  L = 0.01;
R1C = 1/(R1*C);  R3C = 1/(R3*C);
Linv = 1/L; Cinv = 1/C;
a11 = -R2*Linv;
a12 = (4*R2 - 1)*Linv;
a21 = Cinv;
a22 = -(R1C + R3C + 4*Cinv);
A = [ a11 , a12 ; a21 , a22 ];
b = [ Linv ; R1C ];
c = [ 0 , 1 ];
d = 0;
S = ss(A,b,c,d);
t = [ 0 : 5e-8 : 5e-5 ];
u = 10*ones(size(t));
x0 = zeros(2,1);
y = lsim(S,u,t,x0);
plot(t,y)
grid on
return
