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There are two types of field effect transistors:
- junction field effect transistors and
- metal-oxide semiconductor field effect transistors.
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What are the various types of transistors?
TransistorsThe two main types of transistors are the bipolar junction transistor (BJT) and the field-effect transistor (FET). Bipolar Junction TransistorsBJTs can have two different polarities, NPN and PNP. An NPN BJT is one where a positively-doped (P-type) semiconductor is sandwiched between two negatively-doped (N-type) semiconductors. A PNP BJT is, obviously, one where an N-type semiconductor is sandwiched between two P-types. Both types of BJTs have an exponential dependence between the input voltage and the current output. For the record, I should state that a semiconductor is basically a material with conductance between that of an insulator and a conductor. Silicon and germanium are the two most well-known semiconductors. Also, doping just means the addition of impurities into a semiconducting material in order for it to either: increase its electron acceptance (P-type) or increase its electron conductance (N-type). Some specific types of BJTs:HBT - heterojunction bipolar transistor - These types of transistors are very similar to BJTs except that the two P-type semiconductors in the PNP polarity, or the two N-type semiconductors in the NPN polarity, are doped differently relative to each other. The reason for doing this, simply stated, is to make it more difficult for a transistor to operate in the reverse direction from which is was intended.Grown-junction transistor - This was the first type of BJT and is self-explanatory. The PN or NP junctions, depending on whether it's of NPN or PNP polarity, respectively, are grown onto a single, solid crystal of semiconductor material. Grown, in this case, means slowly attached, chemically.Alloy-junction transistor - Similar to a grown-junction transistor except the semiconducting material onto which the PN or NP junctions are grown is specifically germanium.MAT - micro-alloy transistor - An improved, speedier version of the alloy-junction transistor. The materials of the PN or NP junctions of a MAT are metal-semiconductor, as opposed to semiconductor-semiconductor.MADT - micro-alloy diffused transistor - An improved, speedier version of the MAT. The dopant material of a MADT is diffused (thinly spread) accross the entire germanium crystal prior to PN or NP growth, as opposed to a MAT where the doping material is only on the metallic side of the PN or NP junction.PADT - post-alloy diffused transistor - An improved, speedier version of the MADT. A thin, diffused dopant layer of germanium is grown onto the germanium crystal, as opposed to the entire germanium crystal being diffused, which allows the germanium crystal to be as thick as necessary for mechanical strength purposes. The PN or NP junctions are then grown onto this thin layer.Schottky transistor - These are alloy-junction transistors with a Schottky barrier between the metal-semiconductor junction. All metal-semiconductor junctions act sort of like capacitors with a voltage between the junctions. Often, you'd like to minimize this voltage in order to minimize the saturation (the amount of the germanium crystal) needed for the transistor to work. Minimizing the saturation effectively speeds up the transistor's performance, which is great for things like switches. Schottky barriers use various materials to do exactly this.Surface-barrier transistor - These are just like Schottky transistors except that both junctions are metal-semiconductor as opposed to only one.Drift-field transistor - The doping agent of these transistors is engineered to produce a specific electric field. This effectually reduces the electrons' transit time between the junctions of the transistor, thereby making it work faster.Avalanche transistor - These transistors can operate in the breakdown voltage region of a transistor's junctions. The breakdown voltage is simply the minimum voltage in which an insulator starts acting like a conductor. Thus, these transistors allow for higher currents to be applied to them than their normal counterparts.Darlington transistor - These are simply two BJTs connected together to further increase the gain of the current output.IGBT - insulated-gate bipolar transistor - These transistors combine the use of BJTs as switches with an isolated-gate FET (see below) as the input. IGBTs provide much more efficient and faster switching than regular BJTs and are thus some of the most common transistors found in modern appliances.Photo transistor - These transistors convert electromagnetic radiation in the form of visible light, UV-rays, or X-rays into current or voltage. As opposed to the normal PN junctions found in many transistors, photo transistors use PIN junctions. PIN junctions are similar to PN junctions except that they have an additional intrinsic semiconductor between the P-type and N-type semiconducting regions. This intrinsic semiconductor is a very lightly doped semiconductor which exists, at least for the purposes of photo transistors, to supply a region within the junction where a photon (a particle of electromagnetic radiation with a specific energy) can ionize (knock an electron out of via the photoelectric effect) an atom of this semiconducting material. Because of the electric field caused from the surrounding P-type and N-type semiconducting regions, this ionization causes the photoelectron to move toward one end of the junction, thereby producing what's known as a photocurrent, which is then amplified in the same manner as all other BJTs. I promise that the rest of my answer won't get more complicated than this.Field-Effect TransistorsFETs use electric fields to control only one-type of charge carrier, as opposed to BJTs which control both types. Now's as good a time as any to introduce the concept of electron holes. Intuitively, electrons carry negative charge and are thus referred to as negative charge carriers. Well, the absence of an electron where one used to be is called an electron hole. These holes act exactly as electrons do in transistors except that they carry positive charge, in the form of missing negative charge, and are thus called positive charge carriers. FETs are designed to control either positive or negative charge carriers, in the form of holes or electrons, but not both. The flow of positive or negative charge carriers occurs through what's called the channel of an FET. FET channels are created within the bulk material of the FET, which is usually silicon. If you find this idea more complicated than what I wrote about photo transistors, that's only because you haven't looked up the physics behind the photoelectric effect yet. Some specific types of FETs:CNTFET - carbon nanotube field-effect transistor - These FETs use carbon nanotubes instead of silicon as their channel material. Carbon nanotubes are needed as FETs continue to get smaller in size. They help reduce effects, such as quantum tunneling and overheating, which are beginning to become real problems in small, silicon-based FETs.JFET - junction gate field-effect transistor - This FET supplies a voltage accross the charge-carrying channel that can pinch it shut, effectively stopping the current through the channel.MESFET - metal semiconductor field-effect transistor - Similar to, but faster than, JFETs, MESFETs use a Schottky barrier (see above) instead of a PN junction.HEMT - high electron mobility transistor - The FET version of an HBT (see above). Faster than a MESFET, the charge-carrying channel is between two different materials instead of within a single, doped region. Also known as a heterostructure FET (HFET) or a modulation-doped FET (MODFET).MOSFET - metal-oxide-semiconductor field-effect transistor - This is the most basic, and most common, type of FET, analogous to the standard BJT (see above). Instead of pinching its charge-carrying channel shut as in a JFET, a MOSFET has an insulator attached to its input electrode which can be turned on or off depending on whether a voltage is supplied accross it. The channel can be N-type (nMOS) or P-type (pMOS), as explained above under the "bipolar junction transistors" heading.ITFET - inverted-T field-effect transistor - This is simply any type of FET that extends vertically out from the horizontal plane in a T-shape, hence the name.MuGFET - multiple gate field-effect transistor - A MOSFET where more than one input shares the bulk material of the FET. The idea is to use the same FET, thus the same sized object, for multiple things. This concept came about due to the ever shrinking sizes of transistors.MIGFET - multiple independent gate field-effect transistor - A MuGFET where the multiple inputs are independently controlled.Flexfet - A MIGFET with two inputs, one on a JFET and the other on a MOSFET. The JFET and MOSFET are then "stacked" on top of each other. Due to its design, the JFET and MOSFET are coupled to each other; i.e. the channel through one effects the channel through the other and vice versa.FinFET - A MuGFET where the charge-carrying channel is wrapped around a piece of silicon, called a fin. The reason for doing this is similar to that of a PADT (see above); i.e. mechanical strength.FREDFET - fast-recovery (or reverse) epitaxial diode field-effect transistor - A cute name for a transistor which is basically designed to quickly turn off when no more voltage is being supplied to it.TFT - thin-film transistor - An FET where the semiconducting material is placed via thin films over the bulk of the device. This is opposed to the bulk of the device being the semiconductor itself, as in most FETs. The bulk material used in TFTs is often glass. The reason being so that the transistors can work behind a clear display in applications like liquid crystal display (LCD) monitors.OFET - organic field-effect transistor - An FET with an organic polymer semiconductor as its channel. These are like TFTs except the bulk of the device is plastic, allowing for very cool, flexible LCD monitors.FGMOS - floating gate MOSFET - A MOSFET with a "floating gate" input; i.e. an electrically isolated input that can store charge, like a capacitor, to be used later. These are the transistors behind flash drives.ISFET - ion-sensitive field-effect transistor - An FET that changes its current depending on the ion concentration of a solution. The solution itself is used as the input electrode in an ISFET.EOSFET - electrolyte-oxide-semiconductor field-effect transistor - A MOSFET with the metal replaced by an electrolyte solution. EOSFETs are used to in neurochips to detect brain activity.DNAFET - Deoxyribonucleic acid (DNA) field-effect transistor - A MOSFET with its input electrode being a layer of immobilized, single-stranded DNA. The current through the MOSFET is modulated by the varying charge distributions that occur when complimentary DNA strands hybridize to the layer of single-stranded DNA on the input electrode. DNAFETs are used, not surprisingly, in DNA sequencing.My sources all stem from the link below which is also a great place to learn more about transistors.
Do Transistor have a polarity?
Transistors have many characteristics and they most certainly require voltages to be a certain polarity if they are to work properly. There are two main types of transistor: PNP and NPN. They are identical except that all polarities are reversed on one compared to the other. There are many books and online resources that describe transistors but here is a very brief note about transistor operation. Each transistor has a base, a collector and an emitter. When a small current is passed from the base to the emitter, a larger current will pass from the collector the the emitter. With an NPN transistor, the base needs to be positive with respect to the emitter and the collector also has to be positive with respect to the emitter for the transistor to work. A PNP transistor is reversed, where both the base and the collector need to be negative with respect to the emitter to operate. Therefore, transistors do indeed have a polarity, even if it is more complex that some other devices. Disclaimer: The above description of transistor operation is greatly simplified and there are operational modes that are outside the conditions described. Please don't use the above description as a definitive guide to transistor behaviour.
How many states does a transistor have?
A transistor can be in three conditions or states. It can be active (at a voltage higher than the emitter), in saturation or cut off (no current).
In ujt what does the j stand for?
For many people the letters UJT stand for Unitary Junction Transistor.
What are transistors?
Transistors are semiconductor devices which can be used as switches (to turn on and off an electrical signal or current path) and also as a signal amplifier in a circuit. There are two broad types of transistors BJT (Bipolar Junction Transistor) and FET (Field Effect Transistors). - Neeraj Sharma A transistor is a silicon device with 3 leads, emiter, collector, and base. It is used both as a fast switching device and for signal amplification. It is said to be "saturated" when maximum current is flowing and "cutoff" when no current is flowing from the emiter to the collector. It takes a difference of approx. .7 volts between the emiter and base to turn it "on". Good switch but actually inferior in sound quality to its predicessor, the "Thermionic" or good ole vacuum tube. If you don't believe me, listen to a guitarist play through both a transistor and vacuum tube guitar amp. You will be quite amazed!!! For signal amplification the input signal goes into the base and the amplified output signal is taken at the collector with the transistor operating, or biased, between cutoff and saturation. It would be normally biased in between cutoff and saturation for the signal to be "linear" or non distorted. The signal at the collector will be inverted (180 phase shift) with respect to the input signal. There are other applications where the output is taken at the emiter where the signal is not inverted (in phase) with respect to the input signal. This configuration, generally, has no gain or has what is called "unity gain". Sometimes you see this when separate stages need to be impedance matched for maximum efficiency. The transistor is first "biased" or configured for a specific amount of gain and the output signal is taken at the collector with a higher amplitude than the input at the base. A transistor is a semiconductor device used to amplify and switch electronic signals and electrical power . It is composed of semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Today, some transistors are packaged individually, but many more are found embedded in integrated circuits . The transistor is the fundamental building block of modern electronic devices, and is ubiquitous in modern electronic systems. Following its development in 1947 by John Bardeen , Walter Brattain , and William Shockley, the transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, among other things. The transistor is on the list of IEEE milestones in electronics, and the inventors were jointly awarded the 1956 Nobel Prize in Physics for their achievement.
What is the symbol for a transistor?
There are many types of transistors, starting out with the typical Base-Collector-Emmitter type. There are two types, starting with the NPN type, The symbol for these is PNP There are also the FET or Field Effect Transistors and their symbols are below, as well as the PNP and NPN. The FET's are divided into the N channel and J channel types:
What is the application of TTL in integrated circuits?
Transistor transistor logic is one type of many different types of bipolar transistor based digital logic circuitry. It is very efficiently implemented in integrated circuit chips, needs only one power supply voltage, and operates at reasonably high speeds. Transistor transistor logic was first developed in the middle 1960s as a modification of the diode transistor logic, then in use in some digital logic integrated circuit chips but dating back to the earliest discrete bipolar transistor logic developed in the late 1950s and derived from vacuum tube point contact diode logic used in many early first generation computers. Transistor transistor logic integrated circuits dominated the computer and electronic digital controller market from the late 1960s until the middle 1980s, when metal oxide semiconductor field effect transistor based microprocessors and microcontrollers began to replace it. By the early 1990s transistor transistor logic and other bipolar transistor based digital logic integrated circuits had been replaced with equivalent complementary metal oxide semiconductor field effect transistor integrated circuits that were both faster and consumed less power (thus running much cooler) or with programmable logic devices of various types. In general transistor transistor logic is now considered obsolete.
What is direct couple transistor logic?
Direct coupled transistor logic is a type of transistor that is more economical to use then integrated circuits. These transistors can be found in many types of wires such as the ones that control cable internet.
What are FET's used for?
FET's or `field effect transistors' can be used for a variety of purposes from audio to power control. Unlike a regular (bipolar) transistor, they are more efficient and responsive to input voltages. There are several benefits to using FET's and are way too numerous to list here, but they are a very good type of transistor where the applications require additional sensitivity. I've used many different types and prefer using them whenever possible for my personal projects.
How many types of radio's are there?
3 types 1 foxhole radio 2 crystal radio 3 transistor radio
How many junctions does a Field Effect transistor have?
1
What is transistor and how can it operate and what are its types?
A transistor is a semiconductor device used to amplify & switch electronic signals. The name transistor comes from the 'trans' of transmitter and 'sister' of resistor. Transistors are used in a wide array of electronic equipment, ranging from pocket calculators and radios to industrial robots and communications satellites.There are two types of transistor viz:Primary type transistor-The primary type of transistor in use is known as a bipolar junction transistor, which consists of three layers of semi-conductor material, two of which have extra electrons, and one which has gaps in it. The two with extra electrons (N-Type) sandwich the one with gaps (P-Type). These bipolar transistor are divided into NPN and PNP types. All these primary type of transistor are shielded to protect from light source if it is not shielded from light then the light may be used to open or close the gate, in which case it is referred to as a phototransistor, functioning as a highly-sensitive photodiode.Secondary type transistor-The secondary type of transistor is known as a field-effect transistor, and consists either entire of N-Type semi-conductive material or P-Type semi-conductive material, with the current controlled by the amount of voltage applied to the transistor.General process of Transistor WorkingEach transistor has a store of electrical charge that remains there until it is turned on. In order to turn on a transistor, a small electrical charge needs to enter it via the base. When this happens, the electrical charge opens up the collector, and a more powerful charge leaves through the emitter. Electrical charge is measured in milliamps, and the typical transistor will multiply an electrical charge by one hundred times the number of milliamps it has. The electrical charge that is emitted by a transistor will then flow through a route designated by however the component it is attached to is designed. Complex electronics have many paths that electrical currents need to travel on, and therefore many transistors will be needed in order to constantly supply enough power to work the device.
Where one can find a vintage transistor radio?
One can find a vintage transistor radio on many websites online. Amazon sells these types of radios on their website. The price range for the radios go from $15.00-$250.00.
How many types of field hockey surfaces?
4
How many junction that transistor have?
3
How many junction transistor have?
3
How many different types of jobs are there in the medical field?
Please, it is three
