Transistor is kind of scary to many beginners as most commonly, transistors are not given importance than vacuum tubes within twelfth grade course. Here is Kind of List of Common PNP, NPN Transistors For Arduino, Raspberry Pi Projects for the Beginners. Also, in this article, we will discuss basics around transistors. Transistor can be used as a switch or an amplifier. Our guide to use buzzer with IR sensor using a transistor is example of using transistor as amplifier. That is, in general uncommon use. Transistors commonly used as electronic switches. That amplifier usage is common in mobile phones, televisions, sound reproduction, signal processing etc. Usually in digital circuits they work as while in analog circuits they work to amplify signals. In general, transistors allow a larger voltage to flow through the other two leads when small current at the base (another lead) is applied. There are two types of basic transistors, one is bi-polar junction (BJT) and the other is metal-oxide field-effect (MOSFET).
Basics of Common PNP, NPN Transistors
There are really too many articles on the web on basics of how transistors work. Bipolar transistors (BJT) can be directly driven by I/O pins, are cheap and has two variants – NPN and PNP. Transistor has three terminals or leads which correspond to three distinct layers inside. Inside, the layers are arranged like sandwich. The way of layering results transistor to be either P-N-P (PNP) or N-P-N (NPN).
The three terminals or leads or legs are base, emitter (negative lead) which emits the charge carriers and collector (positive lead) which collects the charge carriers. Remember – PC – Positive is Collector.
Other unknown transistors look so different that unlike resistors, diodes; it is practically impossible to identify unless previously known. We commonly deal around those PHP, NPN transistors and MOSFET. What is MOSFET? MOSFET is bigger, older hammer for the same purpose that of NPN and PNP transistors. MOSFETs are more power efficient.
Common PNP, NPN Transistors For Arduino, Raspberry Pi Projects
Transistor kits are sold everywhere from Ebay, Amazon to real life shops, which are boxes of common transistors :
Not much knowledge really required, those peoples are doing the job for many years to decades. Notice the label of box, they has our listed stuffs. There are 100 Pieces kits and enough for hobbyist grade humans.