% C. Talarico
% examplecs.m
% post process LTspice simulation with Matlab
clear all; clc; close all;

filename = 'commonsource.txt';
[nvars blocks points pData] = ltsExp2Matlab(filename);

mR = blocks*nvars; % number of data sets (rows of pData)
nR = points; % number of points in each data set (columns of pData)

pData

freq = pData(1,:);
vout = pData(2,:);
magdb = 20*log10(abs(vout));
phase = 180*unwrap(angle(vout))/pi;

Av0 = abs(vout(1)) % DC gain in V/V
Av0db = magdb(1)   % DC gain in dB
f3db = interp1(magdb, freq, magdb(1)-3, 'spline')

% plots 

figure(1);
subplot(2,1,1);
semilogx(freq,magdb,'linewidth',2);
grid on;
ax = gca;
set(ax, 'fontName', 'Arial Narrow', 'fontsize', 16);
xlabel('freq [Hz]','fontsize',16, 'fontName', 'Arial Narrow');
ylabel(' Gain [dB]','fontsize',16, 'fontName', 'Arial Narrow');
% Annotate title
str1 = sprintf('Voltage Gain vs. Frequency\n');
str2 = sprintf('|DC Gain| = %0.2g dB (%0.2g V/V) - f_{3dB} = %3.2f MHz', Av0db, Av0, f3db*1e-6);
str = {str1,str2};
title(str,'fontsize',18,'fontName', 'Arial Narrow','fontWeight','bold');

subplot(2,1,2);
semilogx(freq,phase,'linewidth',2,'color','m');
grid on;
ax = gca;
set(ax, 'fontName', 'Arial Narrow', 'fontsize', 16);
xlabel('freq [Hz]','fontsize',16,'fontName', 'Arial Narrow');
ylabel('Phase [degrees]','fontsize',16,'fontName', 'Arial Narrow');
title('Phase vs. Frequency','fontsize',18,'fontName', 'Arial Narrow','fontWeight','bold');