Isolated Vs Non-Isolated Power Converters: What is the difference?

Isolation is quite a common term in the field of electronics. It is basically a measure of the ability of an electronic device to resist unwanted electrical and/or magnetic interference. It is a method of reducing undesirable external influences on a circuit.

The isolation can be achieved by using different techniques like capacitance, inductance, or resistance. The choice of these techniques depends upon the nature of the circuit and its requirements.

What are power converters?

In simple words, power converters are the devices that convert direct current (DC) to alternating current (AC), and vice versa. An example of a power converter is your computer’s power supply. You plug it in to a wall outlet, and it converts AC electricity into DC electricity that your computer can use.

What are isolated power converters?

These are power converters that are isolated from the input and output circuits. These are generally used in applications where a circuit needs to be isolated from its environment. The main purpose of using these power converters is to deliver clean power to the circuit, which is free from noise or any other interference.

What are non-isolated power converters?

These are also known as non-isolated DC/DC converters or step-down (buck) converters because they step down the voltage level from a higher DC voltage to a lower DC voltage.

These power converters are used in applications where a DC voltage is required. They are also used in different types of DC to DC power conversions such as battery chargers, solar inverters, and power supplies.

Advantages of isolated power converters

Why are isolated power converters so popular? Well here are the top reasons.

To break the ground loops

In isolated power converters, the input and output sources don’t share a ground. This means that there is no ground loop.

To minimize the noise

The isolated power converters will reduce the noise in the system. As a result, there will be less noise in the system.

To improve efficiency

Since there is no ground loop, you will get more power out of your isolated DC/DC converter as compared to a non-isolated DC/DC converter. This results in more efficiency and minimizes losses.

To improve the output voltage level

By isolating the input and output circuits, you can produce higher output voltages levels as compared to non-isolated DC/DC converters. The increased voltage level can be used by other circuits or devices when they need to operate at higher voltages levels.

To improve the system stability

When the input and output circuits are isolated, there is no ground loop. This means that there will be no voltage drop across the input and output terminals of the DC/DC converter. This will improve the system stability as compared to a non-isolated DC/DC converter.

To reduce the temperature rise in the system

Since there is no ground loop, you can minimize any voltage drop across the input and output terminals of a DC/DC converter. The lower voltage drop across these terminals can result in a reduction in temperature rise due to heat dissipation in the circuit.

Benefits of non-isolated power converters

Advantages of non-isolated power converters

Cost savings:

Due to the fact that the input and output circuits are not isolated, there will be a voltage drop across the input and output terminals. When a DC/DC converter is used in a non-isolated system, this voltage drop will result in power losses. These power losses can be reduced by using DC/DC converters with an isolated input and output circuit.

Small size:

The size of DC/DC converters is a major factor when it comes to selecting the appropriate power supply. In order to reduce the size of a DC/DC converter, one needs to use an isolated DC/DC converter. This will enable one to use a smaller-sized DC/DC converter for the power supply in comparison to a non-isolated DC/DC converter.

Fewer components

When using an isolated DC/DC converter, there are no external components such as resistors and capacitors that can be added in between the input and output terminals of the DC/DC converter. This will mean that you will have fewer components in your circuit as compared to a non-isolated circuit. This will result in a smaller circuit size and fewer components.

Lower noise

Whenever there is an electrical component that is connected to the input and output of a DC/DC converter, this will increase the noise in the system. However, when a DC/DC converter is isolated, the noise is reduced due to the absence of any external components or wires that can be added between the input and output terminals. This will result in a lower noise level in your system.

Applications of isolated vs non-isolated power converters

What is an isolated power converter used for?

An isolated power converter is used when a device or circuit requires continuous DC power, but does not have its own internal source of DC electricity. For example, a computer system uses DC electricity to run its chips.

But the computer does not have an internal power supply to generate DC electricity. That’s why you need an external power supply to convert the AC voltage from the wall outlet into DC voltage that can be used by the computer’s chips.

On the other hand, non-isolated power converters are used for applications where it is important to have an output voltage as such.

Non-isolated power converters are suitable for applications that require a high level of performance from the converter. These converters are designed so that they can work with a wide range of inputs and outputs.

They are also suitable for applications like portable equipment, where size, weight, and battery life are important considerations.

They are also ideal in applications that require some form of lighting.

The output voltage of the power converter is determined by the input voltage and the output current. The output current depends on the voltage. The higher the input voltage, the higher will be the output current.

Which one is efficient?

The efficiency is measured in terms of power factor and percentage of input energy converted into usable energy (power).

In most cases, an isolated converter will operate at a higher percentage than its non-isolated counterpart due to the fact that the output voltage and current will not be affected by the load connected. In case of a non-isolated converter, the output voltage and current will be affected by the load connected.

Buying isolated and non-isolated power converters

It is of no real difference, as long as the requirements of the application are met.

The input voltage is determined by the load which is to be connected to the power converter. The input voltage can be from 5V to 30V. It is important that this voltage should be within a certain range so that it does not cause any damage to the power converter.

In case you are trying to buy a converter, whether isolated or non-isolated, consider using ICRFQ. We are a reputable power converter supplier in China.

If you are a power supply manufacturer and want to get more information about the products we have, please contact us.