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Curve tracer for transistors

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In my previous story , I told you how my students and I made simple curve tracers in the laboratory and used them to study the IV curves of various 2-terminal elements (resistors and diodes). Now I will show you how, in the next exercises, we improved our devices to be able to study transistors. As I have already said, such professional devices exist both for the study of diodes and transistors but they are closed and their internal structure is inaccessible to students. That is why, again I preferred that they design and make curve tracers themselves to understand them. I have been using this approach since 2015, when I had to organize and lead the laboratory exercises on Semiconductor Devices in the ITI department. I have also written this story in Bulgarian . Transistor IV curves Transistors are semiconductor elements with three terminals - base , emitter and collector . To get their IV curves, we decompose them into two 2-terminal "elements" - input ( base-emitter ) and

Simple curve tracer for diodes

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In this story, I will tell you how, in the labs of Semiconductor Devices, Basic Circuits and Electrical Engineering, my students made simple curve tracers and used them to study the IV curves of various 2-terminal elements. Basically, such professional devices exist but they are closed and their internal structure is inaccessible to students. That is why, I preferred them to design and make curve tracers themselves to understand them. I have been using this approach since 2015, when I had to organize and conduct the laboratory exercises on the subject of Semiconductor Devices in the ITI department.  I have also written this story in Bulgarian . IV curve Most of the DC elements we work with in the lab have only two terminals. Typical examples are resistors and diodes (silicon, germanium, zener, LEDs, etc.). What are they characterized by?  How can we explore them? The relationship between current and voltage, represented graphically, is called IV curve.  It is accepted that the voltage