How to build a dual power supply for the Operational Amplifiers

Operational Amplifiers (Op-Amps):

You may be aware that in analog electronics Operational amplifiers are widely used as important components for best utility. It is a high-gain voltage amplifier with dual inputs such as inverting and non-inverting. The output is always single-ended. It amplifies the two input voltages and converts them into the difference between the two.  

Exclusive Power Supply Requirements for Operational Amplifiers

A dedicated power supply is required for the correct functionality of the op-amps. Normally a dual power supply is required for the proper functioning. Many op-amps operate with a dual power supply, such as ±12V or ±15V, to handle both positive and negative signal swings effectively. This is common in applications requiring symmetric signal processing. The key aspects of power supply requirements are: 

1. Voltage configuration+12v and -12v dc operation. 

2. Ripple and noise considerations. 

3. Current requirements 

4. Supply voltage range adhering 

5. Decoupling capacitors for stabilized voltage operation 

By adhering to these exclusive power supply requirements, operational amplifiers can achieve optimal performance, ensuring stability, accuracy, and reliability in the designed circuits.

Utility

• Many times operational amplifiers such as IC 741 circuits require dual power supplies.
• Power supplies give positive or negative voltages. 
• Special circuits, such as dual power supplies, produce both positive and negative voltages from the same source. Hence, such circuit designs are preferable for energizing these operational amplifiers. 
• To meet these special needs various dual power supply circuits are available. 
• This post explains a dual power supply circuit using a full-wave rectifier combination. It is simple and easy to construct and low-cost, as it uses very few components. 
• This circuit gives the Operational Amplifier gadgets more steady and sufficient current capacity.
• To learn more about Op-amplifiers click here.

Know your circuit:

Below is a simple, easy-to-build dual power supply circuit schematic for your construction and use in projects utilizing IC 741.  

The circuit schematic:



Parts List

A suitable power supply circuit is shown above utilising the following components in assembling the circuit design.

1. PT - Step down Power Transformer - 230V/12-0-12V
2. U1 - Bridge Rectifier
3. C1, C2 - 100 MFD 40V Electrolytic Capacitor

Know the design

1. The input voltage of 230 volts AC is stepped down to 12V AC in the secondary, which is center-tapped, giving 12-0-12 Volt AC.


2. U1 is a bridge rectifier that converts 12V AC into 15V DC. It works in full-wave rectifier mode.

3. Centre tap acts as negative terminal as well as positive terminal Common potential when compared to other terminals.

4. As such dual DC supplies are available + 15 volts and -15 volts with respect to common ground

5. C1 and C2 are smoothing capacitors

Know the assembling

The circuit can be easily assembled on the given PCB board as per the layout shown below:

The readymade PCB design shown is a simple assembling base for the circuit schematic. 

If you want to build a circuit for 5V regulated power supply visit this blog by clicking the link.   

Conclusion

Now you have a fair knowledge of Operational Amplifiers (Op-Amps) and their utility values. To energize the circuit, the popular power supply is discussed at length and complete information is provided for assembling the circuit for practical purposes. Any suggestions and valued comments are welcome.