What are are the three possible states of transistor?

We have seen above that transistor can act in one of the three states : cut-off, saturated and active. The state of a transistor is entirely determined by the states of the emitter diode and collector diode [See Above Fig].

How many states can a transistor have?

In this case the transistor operates as a switch: if a current flows, the circuit involved is on, and if not, it is off. These two distinct states, the only possibilities in such a circuit, correspond respectively to the binary 1s and 0s employed in digital computers.

Why does a transistor have 3 terminals?

BJTs have three terminals, corresponding to the three layers of semiconductor—an emitter, a base, and a collector. They are useful in amplifiers because the currents at the emitter and collector are controllable by a relatively small base current.

Why does a transistor have 3 legs?

Most discrete transistors have 3 terminals representing base, collector and emitter for a bipolar junction transistor (BJT) or gate, drain and source for a field effect transistor (FET) or Metal Oxide (Silicon) FET (MOSFET), hence 3 legs or for some power devices a ‘can’ which serves as the heatsink mounting (collector …

Why is transistor important?

Transistors make excellent electronic switches. They can turn currents on and off billions of times per second. Digital computers use transistors as a basic mechanism for storing and moving data.

When would you use a transistor?

One of the most common uses for transistors in an electronic circuit is as simple switches. In short, a transistor conducts current across the collector-emitter path only when a voltage is applied to the base. When no base voltage is present, the switch is off. When base voltage is present, the switch is on.

How many depletion layers are there in a transistor?

two
It has three terminals namely emitter, base and collector. A bipolar junction transistor, shortly termed as BJT is a current controlled device that consists of two PN junction for its function. and there are two areas of depletion.

What are the 3 legs on a transistor called?

The transistor has three legs, the Collector (C), Base (B), and Emitter (E). Sometimes they are labeled on the flat side of the transistor.

Does transistor have resistance?

In today’s world there are two major types of transistors, MOS and Bipolar. Both of them have ohmic resistance at their terminals since they are made of physical materials. Ohmic resistance would be a device that behavs in a way such that the current through it is directly proportional to the voltage applied across it.

What replaced transistors?

Integrated Circuits: The Next Generation The third generation of modern computers is known for using integrated circuits instead of individual transistors. Jack Kilby at Texas Instruments and Robert Noyce at Fairchild are both credited with having invented the integrated circuit (IC) in 1958 and 1959.

What are the three states of a transistor?

To be very specific, a transistor actually does have 3 states: cutoff, triode, and saturation. For use in digital circuits (aka computers), transistors operate in the saturation state, which allows them to essentially act as an “on or off” switch. This is how digital circuits are designed to be physical…

What is the use of transistor in circuit theory?

In the same way, a transistor can be used to create an open circuit between the collector and emitter pins. With some precise tuning, a valve can be adjusted to finely control the flow rate to some point between fully open and closed.

What are the conditions for a transistor to be active?

To operate in active mode, a transistor’s V BE must be greater than zero and V BC must be negative. Thus, the base voltage must be less than the collector, but greater than the emitter. That also means the collector must be greater than the emitter.

What voltage do you need to turn on a transistor?

In reality, we need a non-zero forward voltage drop (abbreviated either V th, V γ, or V d) from base to emitter (V BE) to “turn on” the transistor. Usually this voltage is usually around 0.6V. Amplifying in Active Mode Active mode is the most powerful mode of the transistor because it turns the device into an amplifier.