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What are the two classifications of transistors?
The two basic types of transistors are the NPN transistorand the PNP transistor. Certainly there are many other semiconductor devices, but these are arguably the two basic ones.
Why base of transistor is lightly doped?
The width of the base is very thin to increase the majority carrier concentration gradient in the base region thereby enhancing the diffusion current and also to reduce the number of majority carriers lost due to recombination in the base.
What is the relation between transistor current?
transistor current is dependent on a factor known as Beta of the transistor. a darlington pair has a large Beta(10,000) , a small signal transistor such as the 2n3904 has a small beta of around 100. the beta of a transistor determines the amount of current that flows from collector to emitter ( bipolar transistors) for each amount of current that flows into the base you get a hundred fold increase between collector and emitter (2n3904), so you insert 1 ma (milliamp) into the base, you get 100 ma out the emitter. there is a doped region in the middle of the transistor that expands when current is applied to the base, this expansion allows more current to flow from collector to emitter (npn). there are many types of transistors but they all employ basically the same function. The mathematics involved is a bit more complicated but I speaking in general terms here to avoid getting someone lost.
What can be viva question from the transistor characteristics in common emitter?
Transistor Characteristics1) What is transistor? what are the types of transistors?Ans: Transistor is a three terminal semiconductor device.There are two types of semiconductor i.e,. n-p-n and p-n-p.2) Define n-type and p-type semiconductors.Ans: If an intrinsic semiconductoris doped with pentavalent impurity. Then it is called n-type semiconductors.If it is doped with trivalent impurity then it is called p-type semiconductor.3) What is doping?Ans: Adding trivalent or pentavalent impurity to an intrinsic semiconductor is called doping.4. What are three basic transistor connection modes? Which mode is most preferred? Why?Ans: Common-Emitter, Common-Base & Common-Collector connections.CE mode is most preferred because CE modes gives Highest voltage gain.5. Define current amplification factor of a transistor?Ans: It is defined as ratio of change in collector current to change in base current.7. What is the biasing rule of transistor?Ans: Emitter base junction should be forward biased and collector base junction should be reversed biased.8. What is semiconductor?Ans: Semiconductor is a substance which has the resistivity in between that of conductor and insulator. semiconductor has negative temperature coefficient of resistance.9) Which are the commonly used semiconductors?Ans: Germanium & Silicon
What is the difference between upstream and downstream in electrical network?
Generally upstream is closer to the positive (+) voltage source. In the case of an NPN transistor upstream of the transistor is the part of the circuit from (+) to the NPN collector pin. Downstream of the transistor is from the NPN emitter pin to the ground / sink / negative (-) terminal.
How many doped regions in a Bipolar transistor?
3: emitter, base, collectorThere are three regions but to be absolutely picky I think only two of them need be doped.Nope: they MUST be doped NPN or PNP. If any are undoped it will not function as a transistor.
What are the functions of pnp?
In what sense? In transistor jargon, p stands for positively doped type and n for negatively doped semiconductor. Another terminology used in mobile games is Pass 'n play.
Why emitter is heavily doped and base is lightly dopped working of p-n-p transistor?
Emitter is heavily doped because to provide charge carriers to Base & Collector region, Base and Collectors are lightly doped because to accept those charge carriers.
Difference between NPN and PNP?
NPN and PNP are transistor types. The difference in the way the layers of semiconductor material are doped with impurities.
Can an PNP transistor be converted to NPN?
No. The NPN transistor is a semiconductor crystal that was "doped" with n-type dopant, then p-type dopant, and then n-type dopant during manufacture. Just the opposite is true for the PNP transistor. Once it's made, it can't be "unmade" to change it.
What kind of material is a transistor made from?
The class of materials that make up transistors is "semiconductor." A transistor is often made from very pure silicon that is doped with germanium or other dopant to change its electrical properties.
What are the two classifications of transistors?
The two basic types of transistors are the NPN transistorand the PNP transistor. Certainly there are many other semiconductor devices, but these are arguably the two basic ones.
Why base of transistor is lightly doped?
The width of the base is very thin to increase the majority carrier concentration gradient in the base region thereby enhancing the diffusion current and also to reduce the number of majority carriers lost due to recombination in the base.
What is formed when part of a material is doped n-type and part of it is p-type?
if the two parts are next to each other, a junction. if not, nothing.
What is the difference between phosphorus doped and gallium doped semiconductors?
phosphorus doped semiconductor will be N type.gallium doped semiconductor will be P type.There are also other differences due to the different size of the dopant atoms.
What is transistor C1061?
This is a shortened form of the part number. The full part number would be 2SC1061.
Why Pmos transistor is usually larger than Nmos transistor in layout?
Due to differences in carrier mobility between P and N type semiconductor, for similarly doped channels the channel of a PMOS FET will be a bit wider than the channel of an NMOS FET so that they both have identical channel resistance. To make the channel wider the PMOS FET will take a larger chip area.
