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Doc/main.bib Normal file
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@book{Horowitz_Hill_2022, place={Cambridge}, title={The Art of Electronics}, publisher={Cambridge University Press}, author={Horowitz, Paul and Hill, Winfield}, year={2022}}
@misc{Onsemi_2022, title={BS170 Data Sheet}, url={https://www.onsemi.com/pdf/datasheet/mmbf170-d.pdf}, journal={Field Effect Transistor - N-Channel, Enhancement Mode}, publisher={Semiconductor Components Industries LLC}, author={Onsemi}, year={2022}, month={Apr}}

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An example circuit and a couple of components are provided and mandatory to use, such as the inductor, the capacitor and the MOSFETs. Apart from these components, the circuit can be altered and or extended to the student's liking to improve its function as long as the final circuit is able to deliver the required current and voltage. An example circuit and a couple of components are provided and mandatory to use, such as the inductor, the capacitor and the MOSFETs. Apart from these components, the circuit can be altered and or extended to the student's liking to improve its function as long as the final circuit is able to deliver the required current and voltage.
\section{Circuit Description} \section{Circuit Description}
%% TODO: ref to AOE third edition According to The Art of Electronics \cite{Horowitz_Hill_2022}, the simplest implementation of a step-up or boost converter consists of just four components; An inductor, a switch, a diode and a capacitor connected as follows:
The simplest implementation of a step-up or boost converter consists of four components; An inductor, a switch, a diode and a capacitor connected as follows:
\begin{Figure} \begin{Figure}
\centering \centering
\includegraphics[scale=0.5]{AOE_BOOSTCONV.png} \includegraphics[scale=0.5]{AOE_BOOSTCONV.png}
@ -75,12 +74,12 @@
\label{fig:boost_converter} \label{fig:boost_converter}
\end{Figure} \end{Figure}
The Art of Electronics describes the function of a boost converter as follows: It describes the function of a boost converter as follows:
\begin{quote} \begin{quote}
During switch conduction (...) the inductor current ramps up; when the switch is turned off, the voltage at point Y rises rapidly as the inductor attempts to maintain constant current. The diode turns on, and the inductor dumps current into the capacitor. The output voltage can be much larger than the input voltage. During switch conduction (...) the inductor current ramps up; when the switch is turned off, the voltage at point Y rises rapidly as the inductor attempts to maintain constant current. The diode turns on, and the inductor dumps current into the capacitor. The output voltage can be much larger than the input voltage.
\end{quote} \end{quote}
The image below shows the final circuit used, the circuit is a slight modification of the example circuit provided. The image below shows the final circuit used. As shown, the circuit includes just a few modification to the example circuit provided.
\begin{Figure} \begin{Figure}
\centering \centering
\includegraphics[scale=0.38]{SCHEMATIC_FULL.png} \includegraphics[scale=0.38]{SCHEMATIC_FULL.png}
@ -96,8 +95,7 @@
\item The MOSFETs, BS170 series \item The MOSFETs, BS170 series
\end{list} \end{list}
%% TODO: Ref datasheet In the example circuit, there was only one MOSFET and it was directly controlled by the MCU. This circuit was able to reach a voltage of $7.5V$, but not at the required current. This is due to the fact that the BS170 series MOSFET has a fairly high $R_{DS(on)}$ of $1.2\Omega$ \cite{Onsemi_2022}. To increase the output current, a second MOSFET was added to the circuit. This way, the $R_{DS(on)}$ is halved, effectively doubling the current at which the inductor can be charged if we neglect the resistance of the inductor itself. The downside of adding a second MOSFET is that it also doubles its input capacitance, however, with an additional circuit modification this can be overcome.
In the example circuit, there was only one MOSFET and it was directly controlled by the MCU. This circuit was able to reach a voltage of $7.5V$, but not at the required current. This is due to the fact that the BS170 series MOSFET has a fairly high $R_{DS(on)}$ of $1.2\Omega$. To increase the output current, a second MOSFET was added to the circuit. This way, the $R_{DS(on)}$ is halved, effectively doubling the current at which the inductor can be charged if we neglect the resistance of the inductor itself. The downside of adding a second MOSFET is that it also doubles its input capacitance, however, with an additional circuit modification this can be overcome.
A second addition to the circuit is the push-pull driver on the gate of the MOSFETs. The driver consists of two NPN transistors that are controlled by inverted signals from the MCU, this way the MOSFET gates are quickly switched between $0V$ and $3.3V$. The push-pull driver was chosen over a pull-down resistor because it would cause several issues; A low resistor value would quickly discharge the gate capacitance, but it would also decrease the driving current when turning the MOSFET on. A high resistor value would have little effect on the gate capacitance. The push-pull driver solves both of these issues by quickly discharging the gate capacitance by connecting them to ground while not effecting the driving current when turning the MOSFET on. This way, the MOSFETs are switched faster, increasing the efficiency of the circuit. A second addition to the circuit is the push-pull driver on the gate of the MOSFETs. The driver consists of two NPN transistors that are controlled by inverted signals from the MCU, this way the MOSFET gates are quickly switched between $0V$ and $3.3V$. The push-pull driver was chosen over a pull-down resistor because it would cause several issues; A low resistor value would quickly discharge the gate capacitance, but it would also decrease the driving current when turning the MOSFET on. A high resistor value would have little effect on the gate capacitance. The push-pull driver solves both of these issues by quickly discharging the gate capacitance by connecting them to ground while not effecting the driving current when turning the MOSFET on. This way, the MOSFETs are switched faster, increasing the efficiency of the circuit.
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\section{Conclusion} \section{Conclusion}
\lipsum[3-4] \lipsum[3-4]
\end{multicols} \end{multicols}
\bibliographystyle{IEEEtran}
\bibliography{main}
\end{document} \end{document}