Quick Answer: What Are BJTs Used For?

Are transistors used today?

By far the most common application of transistors today is for computer memory chips—including solid-state multimedia storage devices for electronic games, cameras, and MP3 players—and microprocessors, where millions of components are embedded in a single integrated circuit..

What is the common types transistor?

Transistors are basically classified into two types; they are Bipolar Junction Transistors (BJT) and Field Effect Transistors (FET). The BJTs are again classified into NPN and PNP transistors. The FET transistors are classified into JFET and MOSFET.

What is an example of a transistor?

The definition of a transistor is an electronic device that works by controlling the flow of the electrical current. An example of a transistor is something combined in large numbers with microcircuits into a single circuit board and used in a computer.

Which of the following best describes a transistor?

A transistor is a device that regulates current or voltage flow and acts as a switch or gate for electronic signals. Transistors consist of three layers of a semiconductor material, each capable of carrying a current. … A transistor regulates current or voltage flow and acts as a switch or gate for electronic signals.

Which transistor is best for switching?

Best Transistors: BJTs#1 NPN – 2N3904. You can find most often NPN Transistors in low-side switch circuits. … #2 PNP – 2N3906. For high-side switch circuits, you need a PNP style BJT. … #3 Power – TIP120. … #4 N-Channel (Logic Level) – FQP30N06L.Apr 21, 2014

When would you use a Mosfet?

The infinite high input impedance makes MOSFETs useful for power amplifiers. The devices are also well suited to high-speed switching applications. Some integrated circuits contain tiny MOSFETs and are used in computers. Because the oxide layer is so thin, the MOSFET can be damaged by built up electrostatic charges.

Where are BJTs used?

Bipolar junction transistors (Also known as BJTs) can be used as an amplifier, filter, rectifier, oscillator, or even a switch, which we cover an example in the first section. The transistor will operate as an amplifier or other linear circuit if the transistor is biased into the linear region.

What are the main uses of transistors?

Transistors are commonly used in digital circuits as electronic switches which can be either in an “on” or “off” state, both for high-power applications such as switched-mode power supplies and for low-power applications such as logic gates.

Why are transistors so small?

They’re made of silicon, the second-most abundant material on our planet. Silicon’s atomic size is about 0.2 nanometers. Today’s transistors are about 70 silicon atoms wide, so the possibility of making them even smaller is itself shrinking.

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.

What is the principle of transistor?

A transistor consists of two PN diodes connected back to back. It has three terminals namely emitter, base and collector. The basic idea behind a transistor is that it lets you control the flow of current through one channel by varying the intensity of a much smaller current that’s flowing through a second channel.

What are the 2 types of transistors?

Basic Electronics – Types of TransistorsThe primary transistor is the BJT and FET is the modern version of transistor. Let us have a look at the BJTs. … The types of BJT are NPN and PNP transistors. … The FET is a unipolar device, which means that it is made using either p-type or n-type material as main substrate. … Source.

What is transistor with diagram?

Diagram ‘A’ shows an NPN transistor which is often used as a type of switch. A small current or voltage at the base allows a larger voltage to flow through the other two leads (from the collector to the emitter). The circuit shown in diagram B is based on an NPN transistor.

Can a transistor be used as an amplifier?

A transistor acts as an amplifier by raising the strength of a weak signal. The DC bias voltage applied to the emitter base junction, makes it remain in forward biased condition. … Thus a small input voltage results in a large output voltage, which shows that the transistor works as an amplifier.

How do you identify a transistor?

Pin Identification of Transistors To identify the pins, keep the front flat side facing you and count the pins as one, two etc. In most NPN transistors it will be 1 (Collector), 2 (Base) and 3 ( Emitter ).

What is a transistor symbol?

Transistor Symbols The symbol of NPN and PNP is shown in the figure below. The arrow in the symbol indicates the direction of flow of conventional current in the emitter with forward biasing applied to the emitter-base junction. The only difference between the NPN and PNP transistor is in the direction of the current.

What devices use transistors?

Transistors are also found in pacemakers, hearing aids, cameras, calculators, and watches. Most of these devices draw their power from tiny batteries. Most spacecraft also rely on microchips, and thus transistors.

Can a transistor be used as a switch?

One of the most fundamental applications of a transistor is using it to control the flow of power to another part of the circuit — using it as an electric switch. Driving it in either cutoff or saturation mode, the transistor can create the binary on/off effect of a switch.