Basic Electronics: Bipolar Junction Transistor

BJT (Bipolar Junction Transistor) or simply transistor is bipolar component in which current conduction is due to both type of polarity. Transistor is defined as “when P-type or N-type semiconductor material is sandwiched between opposite type of material, it is called as transistor”. The term transistor refers to transfer-resistor. it is current controlled device. There are two types of transistor 1) PNP transistor 2) NPN transistor the arrowhead direction is always from P to N. by observing the direction, you can judge the type of transistor. Transistor is electronic components which has three terminals namely 1) Collector 2) Base 3) Emitter In the symbol of transistor, the terminal having arrow onto it is called as Emitter. Transistor can be operated in three regions and in these three regions, the working of transistor is different. Following table shows the status of junctions (collector-base & emitter-base) and working of transistor.

image shows Typical NPN transistor symbol. collector-base junction emitter-base junction operating region application of transistor reverse bias reverse bias cut off open switch forward bias forward bias saturation closed switch reverse bias forward bias active amplifier forward bias reverse bias inverse active The some applications of transistor includes amplifier, switch, voltage regulators, oscillators etc... following is the online, multiple choice questions which are useful to polish your knowledge about transistor. you can view your score at the end of test immediately and during test you can check the answer is correct or wrong. I hope you will enjoy the test.