In this writing, will be introduced how to build a five volt power supply.
Most of digital devices work on 5 volt, se we need a 5 volt power supply to power it.
Items you will need:
Here is the circuit
How it works?
First, AC input will be step down by transfomer. To make a positive voltage from AC voltage we need a rectifier which can be built by using 4 diodes. This process is called rectification. Then, we need a capacitor to decrease the ripple voltage. Its better for us to choose a capacitor which have a big capacitance. Next, we need a LM7805 to regulate voltage to 5 volt. This process is called regulation.
Beware, the maximum input of LM7805 is ±20 volt. And the minimum input is 7 volt.