Users' questions

What is the operation of a bipolar transistor?

What is the operation of a bipolar transistor?

Bipolar Transistors are current regulating devices that control the amount of current flowing through them from the Emitter to the Collector terminals in proportion to the amount of biasing voltage applied to their base terminal, thus acting like a current-controlled switch.

How does a bipolar junction transistor work?

Bipolar Transistors Contain Two Types of Semiconductor Material. A base current turns the transistor on like a closed switch and allows a proportional amount of current through the collector. Collector current is primarily limited by the base current, regardless of the amount of voltage available to push it.

How do you bias a bipolar transistor?

Transistor biasing can be achieved either by using a single feed back resistor or by using a simple voltage divider network to provide the required biasing voltage. The following are five examples of transistor Base bias configurations from a single supply ( Vcc ).

When does a bipolar junction transistor forward bias?

The transistor spent half its time in active mode and the other half in cutoff with the input voltage too low (or even of the wrong polarity!) to forward-bias its base-emitter junction. Class B: Bias is such that half (180°) of the waveform is reproduced.

How does reversing external bias work in a PNP transistor?

If you try to understand it, reversing the external bias voltages will forward bias the base-emitter junction of a PNP transistor and reverse bias the base-collector junction. Since the base-emitter junction is forward-biased, holes in the emitter region can move through the base-emitter junction and enter the base region.

What do you need to know about bipolar NPN transistors?

One other point to remember about Bipolar NPN Transistors. The collector voltage, ( Vc ) must be greater and positive with respect to the emitter voltage, ( Ve ) to allow current to flow through the transistor between the collector-emitter junctions.

Which is the reverse active region of a bipolar transistor?

VBC), the device is in the reverse active region of operation • Basically the forward active region with roles of emitter and collector reversed David J. Walkey 97.398*, Physical Electronics: Bipolar Operation (16) Page 14 Reverse Active Region – Minority Carriers