base current is very small and we should apply ainput on base current
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.
as the base current is very small compared to the emitter current,the collector current is nearly equal to the emitter current..
A transistor begin to conduct if the Vbe is ~.6v following an exponential curve therefore non very linear. by biasing it is possible to achieve a linear portion of the load lines
The really radical change in electronics was the invention of the transistor. It was not very pretty, it was not very big, but the world was made a far better place because of it
No, it is not possible because in transistor the depletion layers formed in Emitter-Base Junction & Collector-Base Junction are penetrable by both current carriers but in this case of two diodes; the formed depletion region are not penetrable for current carriers (hole &electron). Also, a transistor works only because the base layer is very thin. You won't get that thin layer between emitter and collector just by connecting two diodes together. This thin base layer places the Emitter and Collector in very close proximity to each other. This allows majority carriers from the emitter to diffuse as minority carriers through the base into the depletion region of the base-collector junction, where the strong electric field collects them. In other words the emitter/base current flow draws some of the barrier charge away from the collector/base junction and allows collector/emitter current to flow across the base using minority carriers. So transistor action is not possible. But we can make transistor by connecting two diodes and two dependent current sources i.e. Ebers-Moll model of transistor. This is true only when you want to make the transistor act like a on/off switch, but you cannot make this setup of diodes to act like an amplifier. Whereas the transistor also acts as an amplifier too A transistor can act as: (1) on/off switch (2) amplifier. Diode is made up of two layers and one junction. Transistor is made up of three layers and two junctions.
Since the base in an n-p-n transistor is kept very thin, very few electrons get to recombine with holes and escape out of base, most of the electrons are injected from emitter into the collector. As a result, Base-current is very small. Whereas the Collector-current is almost equal to the Emitter-current.
A Darlington pair uses two transistors connected to behave as a single transistor with a very high current gain (beta). Transistor-1 has its collector connected to the collector of transistor-2. Transistor-1 has its emitter connected to the base of transistor-2. The base of transistor-1 with the emitter and collector of transistor-2 is used as a single transistor.
base current is very small and we should apply ainput on base current
Small is relative term, current gain of the transistor decides how small base current would be than collector current. Most of the emitter current of electrons diffuses through the thin base into the collector. Moreover, modulating the small base current produces a larger change in collector current.Small is relative term, current gain of the transistor decides how small base current would be than collector current. Most of the emitter current of electrons diffuses through the thin base into the collector. Moreover, modulating the small base current produces a larger change in collector current.Small is relative term, current gain of the transistor decides how small base current would be than collector current. Most of the emitter current of electrons diffuses through the thin base into the collector. Moreover, modulating the small base current produces a larger change in collector current.
The base is excited by a very low current. That turns the transistor on so that a higher amount of current flow comes out.
Because a transistor's collector current is proportionally limited by its base current, it can be used as a sort of current-controlled switch. A relatively small flow of electrons sent through the base of the transistor has the ability to exert control over a much larger flow of electrons through the collector.
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.
A transistor has three leads, called the base, the collector, and the emitter. The voltage of the base (in relation to the ground) determines whether and how much current flows from the collector to the emitter. An NPN transistor can be off, meaning that there is no (or very little) voltage from the base; partly on, meaning that there is some voltage from the base; or saturated, meaning that it is receiving full voltage from the base. A saturated transistor allows the current to flow from the collector to the emitter unopposed; a partly on transistor provides some resistance; and a transistor that is off provides full resistance. A PNP transistor is similar to an NPN transistor except it performs the opposite function: when it is saturated, the current is fully resisted; when there is no voltage from the base, the current is not at all resisted; and when it is partly on there is some resistance. In sum, a transistor controls the flow between the collector and the emitter based upon the voltage of the base. this is carbage. a transistor is basicaly two diodes back to back base being common TO BOTH DIODES because of inpurity doping on purpose at the depletion region the transistor will control the current flow on the other diode. Once it reaches saturation both diodes conduct therefore current can flow in BOTH DIRECTIONS ACROSS IT.
A transistor is a solid device consisting of two charged semiconductors sandwiching a very thin piece of an oppositely-charged semiconductor. The thin piece might even be a layer of oxidation on the semiconductor surface. These earlier and more sensitive (and delicate) transistors were made of the semiconductor, Germanium. The later, more sturdy transistors were and are made with silicon.
a very thin cell
A very high speed bipolar junction transistor having a metal-semiconductor emitter base junction instead of a semiconductor-semiconductor emitter base junction.