LM78xx and LM79xx are two series of voltage regulator ICs which are widely used in the circuits of Power supplies. Whatever output voltage is required for circuits or projects, you can choose any IC from this series where xx represents the desired output voltage. These ICs come with a lot of built-in features and circuitry therefore they make your overall circuit cost cheap and super easy to build.
In this tutorial, we are making a circuit of an 11V power supply using LM7811 IC. This IC is available in a TO220 transistor package and provides short circuit and overheat protection. The main purpose of this circuit is to convert AC voltage to DC voltage for your circuits and devices.
Hardware Components
The following components are required to make an 11V Power Supply Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | Step-down Transformer | 230V/12V 2A | 1 |
| 2. | Voltage Regulator IC | LM7811 | 1 |
| 3. | Heatsink | – | 1 |
| 4. | Diode | 2A | 1 |
| 5. | Electrolytic Capacitor | 2200µF/50V | 1 |
| 6. | Ceramic Capacitor | 330nF, 100nF | 1, 1 |
| 7. | DC Supply | 11V | 1 |
| 8. | Breadboard | – | 1 |
LM7811 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of LM7811
11V Power Supply Circuit
Working Explanation
We are using a step-down transformer which gives us a voltage of 12V AC, this voltage is passed through a bridge rectifier of 2A and it converts this signal into DC ripple. This DC voltage is now passed through two capacitors for noise cancellation before going into the IC.
The voltage regulator IC now regulates the voltage to give an output of 11 volts DC, this voltage is passed through another capacitor for removal of any residual noise. This circuit requires Heatsink because the IC can become hot during this process
Applications and Uses
Electronic circuits or devices which require an input voltage of 11V DC can use this circuit. This circuit uses very few components it is compact therefore it can be used with a lot of circuits. It is also used for charging batteries of 11V, or with operational amplifiers. It can be used in such applications where low voltage and low current are required.
