started NTC-type.tex

res/plots/script/NTC.m

@@ -1,15 +1,16 @@
 clc, clear, clearvars, close all
 
 % Define temperature range from 260 K to 420 K with intervals of 0.5 K
-T = 100 : 1/2 : 420;
-
-% Calculate the parameter beta using the given resistance values at two temperature points
-beta = log(1.4e3/1e4) / (1/358.15 - 1/298.15);
+T = 100 : 1/2 : 600;
 
 % Set reference resistance and temperature values
 R0 = 1e4;
 T0 = 298.15;
 
+% Calculate the parameter beta using the given resistance values at two temperature points
+beta = log(1.4e3/R0) / (1/358.15 - 1/T0);
+
+
 % Calculate resistance values using the Steinhart-Hart equation
 R = R0 * exp(beta * (1 ./ T - 1/T0));
 
@@ -21,7 +22,6 @@
 f = figure(1);
 f.Position = pos_vector;
 semilogy(T, R), grid on;
-xlim([100 400])
 xlabel("Temperature [K]"), ylabel("Resistance [Ω]"), title("Resistance - Temperature")
 
 f = figure(2);

src/chapters/NTC-type.tex

@@ -0,0 +1,46 @@
+\vspace{30px}\section{NTC thermistors}
+In contrast to the PTC thermistor, there is the negative-temperature-coefficient thermistor. This device reduces its resistivity when the temperature rises.
+
+\todo{Make NTC introduction a little longer}
+
+
+
+
+
+\subsection{Chrateristics}
+The NTC thermistor and the PTC thermistor, even though their functioning is opposite, have the same characteristic equation. As aforementioned, the equation that describes the behavior of the resistance $R$ in relationship with the ambient temperature $T$ is the following \cite{Chen20091103}:
+
+\begin{equation*}
+    R = R_0 \, e^{\, \beta\left( \frac{1}{T} - \frac{1}{T_0}\right)}
+\end{equation*}
+
+\noindent Where $R$ is the resistance at temperature $T$, which should be measured in Kelvin degrees, and $R_0$ is the resistance value measured at operating temperature $T_0$. The $\beta$ coefficient describes the thermister constant which varies on temperature and materials used to build the device. It can be calculated using the same formula described in the PTC thermistors:
+
+\begin{equation*}
+    \beta = \frac{\ln{\frac{R_2}{R_1}}}{\frac{1}{T_2} - \frac{1}{T_1}}
+\end{equation*}
+
+\noindent By assuming that when $T_1 = 298.15 K = 25^\circ C$, $R_1 = 10k\Omega$ and when $T_2 = 358.15 K = 85^\circ C$. $R_2 = 1.4k\Omega$, it is possible to plot the resistance-temperature relationship of a negative temperature coefficient thermistor. As shown in figure \ref{fig:NTC_logarithmic}, the curve shows that as the temperature rises, the resistance value decreases respecting the aforementioned equation.
+
+\begin{figure}[h]
+    \centering
+    \includegraphics[width = .75\textwidth]{../res/plots/NTC_logarithmic.png}
+    \label{fig:NTC_logarithmic}
+    \caption{NTC resistance-temperature logarithmic curve, from -173°C to 326°C.}
+\end{figure}
+
+\FloatBarrier\noindent If the curve is restricted to more realistic temperature values (such as -13°C to 126°C), it's even more evident the inversely exponential curve which is described by the equation of the thermistor (figure \ref{fig:NTC_cartesian}).
+
+\begin{figure}[h]
+    \centering
+    \includegraphics[width = .75\textwidth]{../res/plots/NTC_cartesian.png}
+    \label{fig:NTC_cartesian}
+    \caption{NTC resistance-temperature curve, limited between -13°C and 126°C.}
+\end{figure}
+
+
+
+
+
+\subsection{Applications}
+As the posistor, also the NTC thermistor was used in space applications, specifically in the launch of the ETS-VI satellite and the H-II satellite \cite{Ishikawa1989116}.

src/references.bib

@@ -145,4 +145,41 @@ @ARTICLE{Cheng2014441
 	publication_stage = {Final},
 	source = {Scopus},
 	note = {Cited by: 15}
+}
+
+Scopus
+EXPORT DATE: 22 January 2024
+
+@ARTICLE{Ishikawa1989116,
+	author = {Ishikawa, Kazuo and Hata, Takuoki and Shiraishi, Keiji and Miyama, Masahiko and Hayashi, Teruo},
+	title = {High-reliability thermistors for space applications},
+	year = {1989},
+	journal = {National technical report},
+	volume = {35},
+	number = {4},
+	pages = {116 – 128},
+	url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-0024714373&partnerID=40&md5=126c9849bb927dd55546621f3a7eb266},
+	type = {Article},
+	publication_stage = {Final},
+	source = {Scopus},
+	note = {Cited by: 1}
+}
+
+Scopus
+EXPORT DATE: 22 January 2024
+
+@ARTICLE{Chen20091103,
+	author = {Chen, Chiachung},
+	title = {Evaluation of resistance-temperature calibration equations for NTC thermistors},
+	year = {2009},
+	journal = {Measurement: Journal of the International Measurement Confederation},
+	volume = {42},
+	number = {7},
+	pages = {1103 – 1111},
+	doi = {10.1016/j.measurement.2009.04.004},
+	url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-67349268137&doi=10.1016%2fj.measurement.2009.04.004&partnerID=40&md5=c71c3dc1659773fbad4a5a45774a8ad5},
+	type = {Article},
+	publication_stage = {Final},
+	source = {Scopus},
+	note = {Cited by: 63}
 }