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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.
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What is the difference between capacitor and transistor?
transistor either increase or decrease current bt capacitor stores the energy
Is active is a cutoff region of transistor?
The active region of a transistor is when the transistor has sufficient base current to turn the transistor on and for a larger current to flow from emitter to collector. This is the region where the transistor is on and fully operating.
Which is the largest current in a pnp transistor?
emitter current
What is the purpose of the base of a transistor?
Recombination of negative and positive charge carriers
What percentage of the total current in a transistor flows through the collector?
The total current in a transistor is the emitter current, which is the sum of the collector current and the base current. The ratio of collector current over base current, in linear mode, is beta-DC, or hFe. However, in order for linear mode to be true, the ratings of the transistor must not be exceeded, and the collector current must not be limited by the circuit. Note also that hFe is temperature dependent, and is expressed in the data sheet as a minimum, not an absolute value - it can vary from transistor to transistor.
What the difference between Transistor and resistor?
The difference between a Transistor and a Resistor is that a transistor is designed to amplify the electrical current, whereas a Resistor is designed to reduce the electrical current.
What is the relation between the processing speed of a computer and transistor?
nothing...
What is the relation between α and β of a transistor?
1:1
What is the difference between a switching transistor and an ordinary transistor?
In the switching transistor the output current is controlled by the (current) and this is also called current controlled current device (CCCD). But in ordinary switch we controlled output current physically...
What is the difference between capacitor and transistor?
transistor either increase or decrease current bt capacitor stores the energy
Is active is a cutoff region of transistor?
The active region of a transistor is when the transistor has sufficient base current to turn the transistor on and for a larger current to flow from emitter to collector. This is the region where the transistor is on and fully operating.
What are the function of the transistor?
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.
How does a transistor electronically switch the output on?
A transistor can electronically switch the output by controlling the flow of current between its two terminals, called the collector and emitter. It has a third terminal, called the base, which acts as a control input. When a small current is applied to the base terminal, it influences the flow of current between the collector and emitter terminals, effectively turning the transistor "on" or "off" and allowing it to change the output state.
What is the Relation between temperature and current?
inversly proportional
What is the difference between a transistor used as a switch and an amplifier?
A transistor used as a switch is operated in saturated mode, where the ratio of base-emitter current over collector-emitter current is far more than hFe, or beta gain. The transistor is either fully on or fully off in this mode. A transistor used as an amplifier is operated in linear mode, where the ratio of base-emitter current over collector-emitter current is equal to or less than hFe, or beta gain. The transistor is partially on in this mode, and is operating as a current controlled current sink.
What happens when the base current of a transistor is decrease?
in a properly biased transistor, collector and emitter current also decrease
Which is the largest current in a pnp transistor?
emitter current
