Most electronic projects and circuits are incomplete without a power supply, it is one of the most important parts of any project. Today we are going to make a simple circuit of an 8V power supply using LM7808 IC. This circuit is ideal for those circuits where a fixed 8V is required. It is quite easy to make even if you have just started studying electronics you will easily understand this project.
LM7808 is a three-terminal positive voltage regulator IC that is available in the TO220 transistor package. It is easy to use and has a low cost along with other built-in features like overheat protection, short circuit protection, and current limiting. This IC provides output current up to 1A and output voltage is 8V. In the 78xx IC series xx represents their output voltage.
Hardware Components
The following components are required to make an 8V Power Supply Circuit
| S.no | Components | Value | Qty |
|---|---|---|---|
| 1. | Transformer | 230V/12V 2A | 1 |
| 2. | Voltage Regulator IC | LM7808 | 1 |
| 3. | Heatsink | – | 1 |
| 4. | Bridge Rectifier Diode | 2A | 1 |
| 5. | Electrolytic Capacitor | 2200µF/50V | 1 |
| 6. | Ceramic Capacitor | 330nF, 100nF | 1, 1 |
| 7. | Connecting Wires | – | 1 |
| 8. | Breadboard | – | 1 |
LM7808 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of LM7808
8V Power Supply Circuit
Working Explanation
This circuit is very simple and is using only a few components since this IC has built-in circuitry and doesn’t need many components. To convert the voltage from 230V to 12V we are using a step-down transformer. This voltage will pass through a diode bridge of 2A for the purpose of rectification. The rectified output is further filtered through capacitors for noise cancellation before being fed into IC. The IC will provide a DC voltage of 8 volts which is also filtered by a smoothing capacitor before coming from the output.
Applications and Uses
An 8V power supply is widely used in labs and by students for the circuits that require a fixed 8V DC supply. Other applications can include the following
- Operational Amplifiers
- Dc motors for Toys
- Audio buffering
