Transistors are commonly used as electronic switches, for both high power applications including switched-mode power supplies and low power applications such as logic gates.
When the transistor reaches a base voltage of a certain level the current will no longer increase and the output will be held at a fixed voltage. Because of this property the transistor can have values of input voltage such that the output is either completely off or completely on. The transistor is acting as a switch, and this type of operation is common in digital circuits where only "on" and "off" values are relevant.
FOR A TRANSISTOR TO BE CALLED A SWITCH it must be operating into the saturation area. whereby both diodes are fully forward biased. to saturate a transistor Essex current must flow into the base. how much rules of thumbs beta of 10. Pushing more base current will have the effect of increasing saturation voltage meaning there is a trade off. it is incorrect to assume that the voltage will no longer increase I submit that both diodes will follow an exponential curve.
it acts as a direct switch by usingg a battery. it is also used in transistors
There were vacuum tubes before transistors
A transistor is a device used to switch power between electrical components. Transistors work to amplify existing signals as well as open and close circuits.
operating region of the transistor is the area of the voltage and an electronic configuration in which a transistor can work with its full efficiency. In that operating region transistor can be used easily what above said by harsh is correct...the following may help u further... Based on application the transistor is decided where to lie. for example transistors are made to lie in active region to make it as amplifier. when transistors are used as switch it is made to lie in saturation region(when switch is made as ON) and cut-off region(when switch is made as OFF).....
essentially a switch controlled by an electrical current
npn and pnp transistors have the same operation as one another, they are both switches, pnps may be known as inverted switches because they work on negative voltage supplys and not positive voltage supplies.
like any other semiconductor
Transistors
by saturating the junctions it becomes a low resistance current path from a relatively hi impedance.
In a microprocessor, field-effect transistors behave as electrically-controlled switches.
ECMs use large scale integrated circuits that are usually embedded in epoxy. They do not contain discrete transistors and are generally not designed to be serviced.
Thermal transistor is an efficient heat control device which can act as a heat switch as well as a heat modulator.