clear all;
clc;
close all;

%% Passa baixas
c = 50e-9;
r = 5e2;
f = 0:100:1e7;
w = 2*pi*f;

fc = 1/(2*pi*r*c);
hw = 1./sqrt(1 + (w.*r.*c).^2);
gb = 20*log10(hw);
phi = rad2deg(-atan(w.*r.*c));

hold all
yyaxis left
plot(f,gb,'-r');

yyaxis right
plot(f,phi,'--r');
hold off

h = gca;
set(h,'xscale','log')

%% Passa altas
c = 50e-9;
r = 5e2;
f = 0:100:1e7;
w = 2*pi*f;

fc = 1/(2*pi*r*c);
hw = (w.*r.*c)./sqrt(1 + (w.*r.*c).^2);
gb = 20*log10(hw);
phi = rad2deg(atan(1./(w.*r.*c)));

hold all
yyaxis left
plot(f,gb,'-r');

yyaxis right
plot(f,phi,'--r');
hold off

h = gca;
set(h,'xscale','log')

%% Passa banda
c = 50e-9;
l = 3.3e-3;
r = 5e2;
f = 0:100:1e7;
w = 2*pi*f;

f0 = 1/(2*pi*sqrt(l*c));
q = (f0*2*pi)*l/r;
hw = r./sqrt(r.^2 + (w.*l - (1./(w.*c))).^2);
gb = 20*log10(hw);
phi = rad2deg(-atan((w.*l - (1./(w.*c)))./r));

hold all
yyaxis left
plot(f,gb,'-r');

yyaxis right
plot(f,phi,'--r');
hold off

h = gca;
set(h,'xscale','log')

%% Rejeita faixa
c = 50e-9;
l = 3.3e-3;
r = 5e0;
f = 0:100:1e7;
w = 2*pi*f;

f0 = 1/(2*pi*sqrt(l*c));
q = (f0*2*pi)*l/r;
hw = 1./sqrt(1 + (r./(w.*l - (1./(w.*c)))).^2);
gb = 20*log10(hw);
phi = rad2deg(atan(r./(w.*l - (1./(w.*c)))));

hold all
yyaxis left
plot(f,gb,'-r');

yyaxis right
plot(f,phi,'--r');
hold off

h = gca;
set(h,'xscale','log')