%Matthew Sturm
%MicroSystems Integration
%Independent Project - Thermal Analysis
clc, clear all

%Thermal Resistance of solder joints:
K_s = 53; %W/m-C
L_s = 50e-6; %Height = 50um
A_s = 400*pi*(50e-6)^2; %20x20 solder joints = 400, radius = 50um
R_s = L_s/(K_s*A_s);

%Thermal Resistance of air gap:
K_e = 0.5; %W/m-C
L_e = 50e-6; %Height = 50um
A_e = (2e-2*2e-2)-400*pi*(50e-6)^2; %area of substrate - area of solder joints
R_e = L_e/(K_e*A_e);

%thermal conduction resistance from location of heat generation to the solder joint
K_c = 100; %W/m-C
L_c = 1e-2/20; %Average distance
A_c = (1e-2)*(500e-6); %1cm*500um - side length*thinkness
R_c = L_c/(K_c*A_c);

%Spreading thermal resistance
a = 50e-6; %radius of solder joint
K_TGP = 100; %W/m-C
R_spread = 1/(2*sqrt(pi*a)*K_TGP)/400;

%Thermal Resistance of substrate:
R_TGP = 4.349; %C/W
        %4.349
%Conductive thermal resistance of Arm-Support
L_armsupport = 0.003; %m
A_armsupport = 0.00194; %m^2
%K_armsupport = ???
%R_armsupport = L_armsupport/(K_armsupport*A_armsupport)

%Thermal Resistance of Arm-Support:
DT = 100-38; %deg C
Power = 3; %W
R_armsupport = DT/Power - ((R_e*(R_c+R_s+R_spread))/(R_e+R_c+R_s+R_spread) + R_TGP)
%Thermal conductivity of arm-support
K_armsupport = L_armsupport/(R_armsupport*A_armsupport)