5V Power Supply using 7805 Voltage Regulator

In this project, I will show you a 5V Power Supply using an integrated circuit 7805 Voltage Regulator, which gives a constant positive 5V DC supply from 6-12V AC or DC. It can be used in any electronics module, Arduino, charger, or circuit board as a fixed linear 5v dc voltage source.

Let's make it!

Component List

The following components are required for this project.

Serial Number Components Name Quantity
1 U1: 7805 IC 1
2 D1,D2,D3,D4: 1N4007 Diode 4
3 C1,C2: 100nF Ceramic Capacitor 2
4 C3: 6.3V, 1200uF Capacitor 1
5 R1: 1KΩ Resistor 1
6 D5: 3mm RED LED 1
7 P1,P2: 2-Pin Terminal Connector 2
8 Aluminum Heat Sink TO-220 1
9 Breadboard /Veroboard 1
10 Connecting Wire -

Circuit Diagram

The schematic of the 5V Power Supply circuit with 7805 Voltage Regulator IC is shown below.

Working Explanation

The working principle of the 7805 voltage regulator based 5V power supply circuit is simple. The 7805 IC is a member of the 78xx series of voltage regulator ICs.

When the circuit gets input ac voltage, the diode bridge (D1,D2,D3,D4) converts to the dc voltage. This unregulated voltage is immediately regulated by the voltage regulator IC (U1), and lots of energy is exhausted in the form of heat.

Two ceramic capacitors (C1,C2) are used with the IC (U1) to bypass tiny extent spikes to the ground. A LED (D5) is used with a protective resistor (R1) for power indication. A capacitor (C3) is used parallel with the output to filter the voltage.

As a result, we get a fixed linear 5V DC supply.

IC 7805 Pinout Configuration

The pinout configuration of the 7805 IC is as follows:

Pin Number Pin Name Description
1 Input (VIN) Unregulated Input Voltage
2 Ground (GND) Connected to Ground
3 Output (VOUT) Regulated Output Voltage


I followed the circuit diagram and assembled the components on a breadboard. Next, I connect the secondary wire of a 230V/12V 500mA step-down transformer to the circuit input.

Here, you can input 500mA to 1.5A and 6V to 12V AC or DC. It is better to keep the input voltage 2 to 3V greater than the output voltage, or a suitable aluminum heat sink should be placed with the 7805 Voltage Regulator IC (U1) to dissipate excess heat.

Demo and Testing

In this demo video, you will see the test of the 5V power supply circuit with 7805 Voltage regulator. Where, I simply powered the circuit by a 500mA 12V AC source from a step-down transformer and the circuit converted the unregulated input voltage to regulated fixed 5V DC.

No comments

If you have any doubts or questions, please let me know. Don't add links as it goes to spam. Share your valuable feedback. Thanks