# How does bipolar transistor function as a switch?

## How does bipolar transistor function as a switch?

The transistor can be used as a switch if biased in the saturation and cut-off regions. This allows current to flow (or not) in other parts of a circuit. Because a transistor’s collector current is proportionally limited by its base current, it can be used as a sort of current-controlled switch.

## How a transistor can be used as a on off switch?

A transistor can be used as a solid state switch. If the transistor is operated in the saturation region then it acts as closed switch and when it is operated in the cut off region then it behaves as an open switch. The transistor operates as a Single Pole Single Throw (SPST) solid state switch.

What can a bipolar transistor be used as?

A bipolar transistor is a semiconductor device commonly used for amplification. The device can amplify analog or digital signals. It can also switch DC or function as an oscillator. Physically, a bipolar transistor amplifies current, but it can be connected in circuits designed to amplify voltage or power.

What are the advantages of using a transistor as a switch?

Transistor switch is economical than other switches. It gives trouble free service because of its solid state nature. It has no moving parts and hence there is no tear and wear. It gives noiseless operation.

### When BJT is used as a switch and switch is said to be on?

A switch offers open circuit (infinite resistance) when it is put in ‘OFF’ position and offers short circuit (zero resistance) when it is put in ‘ON’ position.

### How do you connect a transistor as a switch in a circuit?

To connect the transistor as a switch in a circuit, we connect the output of the device that will switch on the transistor to the base of the transistor. The emitter will connect to ground of the circuit. And the collector will connect to the load that the transistor will turn on and the supply voltage of the circuit.

Which configuration of transistor is used as a switch?

Common-emitter configuration
The most commonly used transistor configuration for use as a switching device is the Common-emitter configuration. Explanation: Transistor: A semiconductor device used to amplify or switch electronic signals and electrical power is called a transistor.