%% ETG 2021/22 - practical class 03
%% 2022-03-08  12:30 A002
%temperature dependency of materials

%Temperature chambre Sunders 4220A
%Multimeters  UT71B

%Si diode 1N4148 https://www.farnell.com/datasheets/3449665.pdf
%NTC thermistor 
%Pt100  https://www.lhotsky-elektro.cz/fotky73031/fotov/CRZ_series.pdf
%resistor metal oxide 180 Ohm; 1%; 0,6 W
%resistor wire-wound (manganin?) 150 Ohm; 5%; 5 W
%Cu wire (relay coil)

%%measured data
temp = [70 70 60 60 50 50 40 40 30 30 20  20 10 10 0 0 -10 -10 -20 -20 -30 -30 -40 -40 -50 -50 -60 -60];
R = [0.5432 1.5249e3 126.94 179.14 149.29 120.29; %70
    0.5421 1.5254e3 126.94 179.14 149.29 121.19;
    0.5604 2.234e3 123.07 179.14 148.85 119.34; %60
    0.5605 2.225e3 123.03 179.14 148.95 118.51;
    0.5788 3.325e3 119.32 179.18 148.69 115.91; %50
    0.5791 3.325e3 119.32 179.14 148.74 115.04;
    0.5982 5.085e3 115.57 179.13 148.55 111.63; %40
    0.5985 5.095e3 115.52 179.05 148.55 110.65;
    0.6173 7.946e3 111.71 179.13 148.35 107.03; %30
    0.6173 7.935e3 111.81 179.13 148.43 107.82;
    0.6369 12.736e3 108.00 179.14 148.25 103.04; %20
    0.6369 12.728e3 107.99 179.10 148.29 103.52;
    0.6561 20.60e3  104.19 179.12 148.14 99.08; %10
    0.6561 20.60e3  104.10 179.12 148.15 98.76;
    0.6755 35.23e3  100.29 179.13 147.95 94.89; %0
    0.6756 35.23e3  100.29 179.13 148.00 95.51;
    0.6958 61.5e3   96.08  179.09 147.75 91.46; %-10
    0.6960 61.4e3   96.08  179.09 147.79 91.10;
    0.7196 111.5e3  92.28  179.05 147.65 87.44; %-20 °C
    0.7223 111.6e3  92.31  179.10 147.61 87.35;
    0.7470 0.2086e6 88.40  179.10 147.6  82.72; %-30
    0.7461 0.2082e6 88.36  179.04 147.6  82.84;
    0.7534 0.4130e6 84.55  179.13 147.6  78.84; %-40
    0.7534 0.4130e6 84.59  179.14 147.6  78.32;
    0.7731 0.8526e6 80.70  179.08 147.55 74.47; %-50
    0.7750 0.8526e6 80.70  179.09 147.55 74.11;
    0.7958 1.8622e6 76.79  179.12 147.45 70.87; %-60
    0.7937 1.9005e6 76.73  179.08 147.49 71.11];

%% calculation of thermal coefficients
shouldBe = [-1.45e-3 NaN 0.00392 5e-6 50e-6 0.0039].*1e6;
for k = 1:size(R,2)
    p = polyfit(temp,R(:,k),1);
    TCR = p(1)/p(2)*1e6;
    txt{k} = ['R0 = ' num2str(p(2),5) ' Ohm;  TCR = ' num2str(TCR,4) ' ppm/K  (' num2str(shouldBe(k)) ')'];
    disp(txt{k})
end

%% graph
figure(1)
subplot(3,1,1)
h = plot(temp(1:size(R,1)),R(:,3),'s-', temp(1:size(R,1)),R(:,4),'d-',...
    temp(1:size(R,1)),R(:,5),'v-', temp(1:size(R,1)),R(:,6),'.-');
xlabel('temp (°C)')
ylabel('R (Ohm)')
legend('Pt100','Resistor metal oxide','Resistor wire-wound','Cu wire','Location','southeast')
grid on
zoom on
for k = [3 4 5 6]
    ind = 2*13;
    text(temp(ind),R(ind,k),txt{k},'Color',get(h(k-2),'Color'), 'VerticalAlignment','Top')
end

subplot(3,1,2)
plot(temp(1:size(R,1)),R(:,2)./1000,'o-')
xlabel('temp (°C)')
ylabel('R (Ohm)')
legend('NTC thermistor 10k')
grid on
zoom on

subplot(3,1,3)
h = plot(temp(1:size(R,1)),R(:,1),'*-');
xlabel('temp (°C)')
ylabel('U_F (V)')
legend('Si diode 1N4148','Location','southwest')
grid on
zoom on
k = 1;  %diode U_F  column
text(temp(ind),R(ind,k),txt{k},'Color',get(h,'Color'), 'VerticalAlignment','Top')