Voltage Divider

Voltage Divider:



What is meant by a voltage divider?

Definition:

                   A resistor or series of resistors provided with taps at certain points and used to provide various potential differences from a single power source.

Circuit Diagram:

Description:

As simple as useful. the voltage divider can be used to:

-set a precise voltage reference;

-make an R to V converter;

-decrease the amplitude of a voltage signal.                    


Current:

Output Voltage:
The output voltage is equal to the voltage drop across R2, which can be found by multiplying the current given by the previous formula with R2.

Importance of a voltage divider:

A voltage divider is one of the basic circuits used in electrical engineering. This is an important concept especially when more complex circuits are to be created. It allows engineers to analyze resistance and to optimize electronic devices. This circuit is one of the important applications of Ohm's Law.

Questions:

1)Why is it called voltage divider?
Answer: With respect to a common point or ground, usually 0V, or it could be across a dual supply, 
for example ±5V, or ±12V, etc. Voltage dividers are also known as potential dividers, because the unit of voltage, the “Volt” represents the amount of potential difference between two points.

2)How does a voltage divider affect current?
Answer: Here is a simple but useful tip to calculate the voltage and current from resistor chains. If the power supply is 12 volts, you will get 4 Volts from the same divider. If we use 200 ohms for R1 and 100 ohms for R2, same output voltage will be obtained, but current will be more.

3)Why do we use voltage divider bias OR
Advantages of the Voltage Divider Bias?
Answer: The resistors help to give complete control over the voltage and current that each region receives in the transistor. And the emitter resistor, RE, allows for stability of the gain of the transistor, despite fluctuations in the β values.

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